ALBERT

Description: 2-Pivaloylpterin, an acylated derivative of the biochemically relevant pterin [2-amino-4-oxo-(3 H )pteridine] heterocyclus, undergoes stepwise metallation by the 1, 1′-bis(diphenylphosphanyl)ferrocene-copper(I) cation, [(dppf)Cu] + . The final product obtained, [Cu 3 (dppf)(μ 2 -dppf)(PP)(PP-H + )] 2 (BF 4 ) 4 , could be structurally characterized to reveal coordinative saturation with binding of central Cu + ions to N 1 ,N 3 ,O 4 ,N 5 ,N 8 and pivaloyl-O donor atoms.

Description: Abstract . Two coordination polymers, namely, {[Cd(cdpc)(hmt)(H 2 O)] · H 2 O} n ( 1 ), and [Mn(Hcdpc) 2 (4, 4′-bpy)(H 2 O)] n ( 2 ), were constructed by synergistic assembly through the mixed-ligand synthetic strategy (H 2 cdpc = 1-carboxymethyl-3, 5-dimethyl-1H-pyrazole-4-carboxylic acid, hmt = hexamethylenetetramine, and 4, 4′-bpy = 4, 4′-dipyridine). Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Single X-ray diffraction analysis reveals that complex 1 is a 2D 4-connected sql sheet, and complex 2 is an interesting 1D loop chain. The two complexes are further expanded to 3D supramolecular structure through non-covalent bonds. Besides, luminescent properties of two complexes in the solid state and magnetic property of 2 were also investigated.

Description: The chemical preparation, structure, luminescence, and electronic properties are given for a new potassium holmium cyclotetraphosphate KHoP 4 O 12 , a promising optics material for applications. Single-crystal X-ray diffraction analysis shows that the newly synthesized compound crystallizes in the monoclinic system with space group C 2/ c and Z = 4. [P 4 O 12 ] 4– anionic rings and HoO 8 polyhedra display a three-dimensional (3D) framework by corner-sharing. The ten-coordinated potassium atoms are located in the delimited tunnels. KHoP 4 O 12 exhibits the blue light emission under the excitation of 330 nm. To gain further insights into electronic properties of crystal KHoP 4 O 12 , theoretical calculation based on density functional theory (DFT) was performed using the total-energy code CASTEP with the LDA + U approach. The calculated bandgap with U = 3.0–3.5 eV is in good agreement with the experimental measurement.

Description: The facile synthesis, molecular structure, and reactivity of [Cu(C 7 H 7 NH 2 )Cl] 4 ( 1 ) towards dioxygen and derivatives is reported. The compound could easily be prepared in good yields by mixing CuCl and benzylamine under inert conditions in dichloromethane. Surprisingly this copper(I) compound, a copper(I) tetramer with Cu I ··· Cu I interactions of 2.89 Å, was formed instead of an expected cubane cluster. Oxidation reactions led to formation of μ-oxido-species as intermediates, however 1 did not show any catalytic activity in the activation of CH bonds. In contrast it turned out that 1 was quite stable towards oxidation. Analogous reactions with CuBr or CuI were different and neither cluster units or polynuclear copper(I) complexes were obtained.

Description: The effect of different factors, such as pH of the medium (1.5 〈 pH 〈 4.0; 1 × 10 –4 mol · L –1 〈 [SO 4 2– ] 〈 1 × 10 –1 mol · L –1 ), the concentration of extracting agent, temperature and the type of the solvent, on the extraction of vanadium(V) by trioctylamine was studied. It was shown that the extraction of vanadium(V) by trioctylamine at 25 ± 0.5 °C takes place in the pH range 2.0–3.5 and the extracting complex contains decavanadate anion H 2 V 10 O 28 4– and four molecules of the extracting agent. This allows the reaction of vanadium(V) extraction by trioctylamine to be described by the following equation: 2( R 3 NH) 2 SO 4 + H 2 V 10 O 28 4– ( R 3 NH) 4 H 2 V 10 O 28 + 2SO 4 . The effect of the length of the alkyl chain of alcohol (propyl, butyl, isododecyl alcohol) on the homogeneity of the system V V -TOA-toluene-alcohol was investigated. It was established that the solubility of the extracting complexes of vanadium(V) with trioctylamine can be increased by using isododecyl alcohol C 12 H 25 OH as a modifying agent. It was shown that under optimal conditions in the presence of isododecyl alcohol at temperatures above 25 °C in the pH interval 2.0–3.5 trioctylamine extracts vanadium(V) with a high distribution coefficient (lg D V V 〉 2).

Description: The tetraalkyldigallium(II) compound R 2 Ga–Ga R 2 ( 1 ) [ R = CH(SiMe 3 ) 2 ] reacted with amino and hydroxo functionalized carboxylic acids by retention of the Ga–Ga bond and release of CH 2 (SiMe 3 ) 2 . New heterocyclic or cage-like compounds were formed with three, two, or six Ga–Ga bonds in a single molecule. The latter dodecagallium compounds encapsulated THF or dioxane molecules in their molecular cavities (carcerands), the other compounds have up to six THF molecules coordinated by N–H ··· O hydrogen bonds.

Description: Reduction of chalcogen-rich Pb:Ch (1:2) phases in ethane-1,2-diamine ( en ) by elemental alkali metals results in the formation of solutions of [Pb 2 Ch 3 ] 2– of high purity and abundance. In contrast, application of the same reaction conditions to a binary Bi:Te (1:2) phase yields the mononuclear [BiTe 3 ] 3– anion. Instead of the expected [Tl 2 Te 3 ] 4– or [Tl 2 Te 2 ] 2– anions, analogous reactions with a Tl:Te (1:1) phase end up with a C–C-bond cleavage of the solvent en with formation of a salt of the telluridocyanate (N≡C–Te) – anion. Side reactions of en and elemental cesium are presented and metalate solutions are investigated with NMR spectroscopy.

Description: Seven lanthanide containing strand-like coordination polymers and dimeric complexes were obtained in a reversible reaction from 1, 3-thiazole (thz) and Ln Cl 3 ( Ln = La, Ce, Pr, Nd). The reactions do not require activation and render coordination polymers accessible at room temperature, already. The product constitutions depend on the lanthanide and the thiazole-to-halide ratio. For lanthanum and cerium formation of the coordination polymers 1 ∞ [ Ln Cl 3 (thz) 3 ] · thz as well as dimeric complexes [ Ln 2 Cl 6 (thz) 8 ] · 3thz were observed. For praseodymium and neodymium dimeric complexes were observed with and without non-coordinating thz. Upon heating, the compounds release thiazole under re-formation of Ln Cl 3 , the formation reaction thus being a thermally reversible reaction. Compounds and conversion processes were characterized by temperature dependent X-ray powder and single-crystal X-ray diffraction, in-situ temperature dependent gas phase IR spectroscopy, DTA/TG, and elemental analysis.

Description: The structural and vibrational data for the CF 3 XX CF 3 ( X = O, S, Se, Te) molecules were compared using DFT quantum chemistry calculations. The experimental vibrational frequencies and their assignments to the different normal modes of vibration could be confirmed. The data was also used to define a scaled quantum mechanics force field and sets of derived internal force constants for each molecule. A linear relationship between the experimental X – X bond lengths and the corresponding force constants was found. Additionally, some calculations for the mixed molecule CF 3 SOCF 3 were made.

Description: The coordination polymer [Zn(bpdc)(bimb)(H 2 O)] n ( 1 ) [H 2 bpdc = biphenyl-3,4′-di carboxylate, bimb = 1,4-bis(1-imidazol-yl)-2,5-dimethyl benzene] was constructed under hydrothermal conditions. The structure of complex 1 was determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, XRD, IR spectroscopy, and TG analysis. Complex 1 shows an exceptional self-penetrating 4-connected net derived from a threefold interpenetrating 6 3 -hcb subnet. Furthermore, the luminescent property of complex 1 is investigated

Description: The new dithiophosphate anion P 2 S 6 (OEt) 2 2– was obtained from the reaction of commercially available P 4 S 10 with Na 2 S in pyridine, subsequent ethanolysis and isolated as the stable bis(pyridinium) salt 1 . The molecular structure of 1 in the crystal was determined by single-crystal X-ray diffraction and reveals a PSSP dihedral angle of 87.3(1)° within the anion. The compound is a rare representative of a thiodiphosphate anion with a disulfide bridge between the two phosphorus atoms.

Description: The ureates of the alkali metals Na – Cs were synthesized from urea and the metals in liquid ammonia at temperatures below 50 °C. The crystal structures were determined using single-crystal X-ray diffraction. NaCN 2 H 3 O crystallizes in the monoclinic system [ P 2 1 / c , Z = 16, a = 17.529(1) Å, b = 6.4784(5) Å, c = 10.8211(9) Å, β = 96.938(1)°]. All other ureates are orthorhombic, with KCN 2 H 3 O and RbCN 2 H 3 O being isotypic [ Pbca , Z = 8, KCN 2 H 3 O: a = 7.102(4) Å, b = 7.221(4) Å, c = 13.533(8) Å; RbCN 2 H 3 O: a = 7.1973(8) Å, b = 7.3531(8) Å, c = 13.921(2) Å]. CsCN 2 H 3 O adopts a smaller unit cell [ P 2 1 2 1 2 1 , Z = 4, a = 6.3520(3) Å, b = 7.1645(4) Å, c = 9.0911(5) Å]. The ureates of K, Rb, and Cs contain hydrogen-bond networks, the imino nitrogen atom acting as the hydrogen-bond acceptor in CsCN 2 H 3 O. In KCN 2 H 3 O and RbCN 2 H 3 O, however, the carbonyl oxygen atom accepts the hydrogen bonds.

Description: Chromium tricarbonyl η 6 complexes of 3 cyclacene are considered quantum chemically at the levels of B3LYP/6-31G(d), B3LYP/6-31++G(d, p), B3LYP/LANL2DZ, and RF/6-31G(d, p)//B3LYP/6-31++G(d, p). One of the complexes involves the top ring (A-type) and the other one (B-type) makes use of ring of the acene belt of the cyclacene in the complex formation. Energy calculations reveal that B-type complex is more stable than A-type. Some geometrical and quantum chemical properties were obtained. Additionally, vibrational and UV/Vis spectra of the complexes were produced.

Description: Three mononuclear copper(II) complexes of copper nitrate with 2, 6-bis(pyrazol-1-yl)pyridine ( bPzPy ) and 2, 6-bis(3′,5′-dimethylpyrazol-1-yl)pyridine ( bdmPzPy ), [Cu(bPzPy)(NO 3 ) 2 ] ( 1 ), [Cu(bPzPy)(H 2 O)(NO 3 ) 2 ] ( 2 ) and [Cu(bdmPzPy)(NO 3 ) 2 ] ( 3 ) were synthesized by the reaction of copper nitrate with the ligand in ethanol solution. The complexes have been characterized through analytical, spectroscopic and EPR measurements. Single crystal X-ray structure analysis of complexes 1 and 2 revealed a five-coordinate copper atom in 1 , whereas 2 contains a six-coordinate (4+2) Cu II ion with molecular units acting as supramolecular nodes. These neutral nodes are connected through O–H ··· O(nitrate) hydrogen bonds to give couples of parallel linear strips assembled in 1D-chains in a zipper-like motif.

Description: The organic-inorganic hybrid compounds, [Cu 2 Cl 6 ] 2– ( 1 ), [Fe 2 Cl 6 O] 2– ( 2 ), and [FeCl 4 ] – ( 3 ), based on [(C 8 H 12 NO)(18-crown-6)] + (C 8 H 12 NO = 4-methoxybenzylammonium) supramolecular cations, were synthesized and structurally characterized. Crystal structure analyses and thermal and dielectric studies showed that compounds 1 and 2 have similar crystal packings and undergo reversible phase transitions at 230 K and 358 K, respectively. Compound 3 shows a phase transition at 361 K, though its crystal structure is remarkably different from 1 and 2 . These results indicate that the phase transitions may arise from the [(C 8 H 12 NO)(18-crown-6)] + supramolecular cations. The role of the chlorometalate anions is to tune the crystal packings and thus the phase transition points and types.

Description: The chemical bonding in the intermetallic compounds ZnPd and ZnPt with the tetragonal CuTi type of structure, and in the chemically related intermetallic compounds ZnNi, ZnCu, ZnAg, and ZnAu with the cubic CsCl type of structure, is examined applying the electron localizability approach. The analysis of the chemical bonding reveals charge transfer from zinc to the transition metal ( TM ), in line with the respective electronegativities. While in ZnNi, ZnCu, and ZnAg as well as ZnPd and ZnPt the Zn– TM interactions are described by multi-center bonding and ionic interactions, mainly ionic interactions are found in the intermetallic compound ZnAu. Going from ZnNi over ZnPd to ZnPt, a gradual change from isotropic to more and more anisotropic distribution of the atomic interactions is detected, resulting in a more pronounced tetragonal distortion.

Description: Two new three-dimensional frameworks with zeolite-like channels were prepared in the presence of 1,6-diaminohexane. Cu 1.5 (H 3 N–(CH 2 ) 6 –NH 3 ) 0.5 [C 6 H 2 (COO) 4 ] · 5H 2 O ( 1 ) crystallizes in the triclinic space group P with a = 772.56(7), b = 1110.36(7), c = 1111.98(8) pm, α = 98.720(7)°, β = 108.246(9)°, and γ = 95.559(7)°. Cu 2 (H 3 N–(CH 2 ) 6 –NH 3 ) 0.5 (OH)[C 6 H 2 (COO) 4 ] · 3H 2 O ( 2 ) crystallizes in the monoclinic space group P2 / c with a = 1159.34(11), b = 1059.44(7), c = 1582.2(2) pm, and β = 106.130(11)°. The Cu 2+ coordination polyhedra are connected by [C 6 H 2 (COO) 4 ] 4– anions to yield three-dimensional frameworks with wide centrosymmetric channel-like voids. Complex 1 reveals voids extending along [100] with diagonals of 900 pm and 300 pm, whereas in complex 2 the diagonal of the nearly rectangular crossection of the channels extending parallel to [001] is 900 pm. The negative excess charges of the frameworks are compensated by [H 3 N–(CH 2 ) 6 –NH 3 ] 2+ cations, which occupy the voids along with water molecules. The [H 3 N–(CH 2 ) 6 –NH 3 ] 2+ cations are not connected to Cu 2+ and have served as templates.

Description: The molecular alumosiloxanes (O-SiPh 2 -O-SiPh 2 -O) 3 Al 2 and (O-SiPh 2 -O-SiPh 2 -O) 4 [Al(OH)] 4 react either with water in diethyl ether, or with 1,4-butane-diol to form the new macro-cyclic compounds Al 6 (OH) 8 (O-SiPh 2 -O-SiPh 2 -O) 4 (O-SiPh 2 -O-SiPh 2 -OH) 2 ·6H 2 O ( 2 ) or Al 6 (OH) 8 (O-SiPh 2 -O-SiPh 2 -O) 4 (O-SiPh 2 -O-SiPh 2 -O-CH 2 –CH 2 –CH 2 –CH 2 –OH) 2 ( 3 ). As shown by single crystal structure analyses, both compounds 2 and 3 have a center of symmetry, resemble each other structurally and display in their center an [Al 2 (OH) 8 ] 2– unit, which is coordinated in a similar fashion to a 24-membered [Al 4 (O-SiPh 2 -O-SiPh 2 -O) 4 ] 2+ cycle branched at two aluminum atoms displaying either two (O-SiPh 2 -O-SiPh 2 -OH) ( 2 ) or two (O-SiPh 2 -O-SiPh 2 -O-CH 2 –CH 2 –CH 2 –CH 2 –OH) ( 3 ) arms. The [Al 2 (OH) 8 ] 2– groups are connected to the cycles through oxygen atoms of their hydroxide groups which link to the aluminum atoms of the ring (of the four aluminum atoms in the ring two have a double contact and two a single). Parallel to this bonding, the aluminum atoms of [Al 2 (OH) 8 ] 2– have either a water molecule in their coordination sphere, which is incorporated in a complex hydrogen bridged network including the silanol function ( 2 ), or are bonded to the –CH 2 -OH group of the siloxane-alcohol arm of the cycle ( 3 ). The aluminum atoms of the central part are in both compounds in the centers of two distorted edge sharing oxygen octahedra (mean Al–O = 1.881(7) Å ( 2 ), 1.893(7) Å ( 3 )), while the other four aluminum atoms display a tetrahedral oxygen environment (Al–O = 1.752(8) Å ( 2 ), 1.754(8) Å ( 3 )). Whereas all hydroxy groups of the [Al 2 (OH) 8 ] 2– unit in 2 are engaged in hydrogen bonding including further water molecules which make part of the network, the [Al 2 (OH) 8 ] 2– unit in 3 shows fewer hydrogen bridges. We have here a rare example of the same chemical species in a more hydrophilic and a less hydrophilic surrounding. This allows a detailed study of the impact of secondary hydrogen bonding on the structure.

Description: The mechanochemical synthesis offers an easy access to obtain alkaline earth metal terephthalates M (C 8 H 4 O 4 ) · n H 2 O ( M = Ca, Sr, Ba). In the presented study we describe for the first time the mechanochemical synthesis of powders of Ca(C 8 H 4 O 4 ) · 3H 2 O, Ca(C 8 H 4 O 4 ), Sr(C 8 H 4 O 4 ) · H 2 O, and Ba(C 8 H 4 O 4 ), which so far were only synthesized as single crystals from aqueous solutions or by reactions in an autoclave. Furthermore, a new hydrate Ba(C 8 H 4 O 4 ) · 2(1.5)H 2 O, not described so far in the literature, was prepared. All compounds were characterized by X-ray powder diffraction, thermal analysis, elemental analysis, FT-IR, and MAS NMR spectroscopic measurements.

Description: The cage compound Ba 3 Ge 16 Ir 4 crystallizes with the Ba 3 Ge 16 Rh 4 type of crystal structure, which represents a hierarchical derivative of the BaAl 4 type. The crystal structure [Pearson symbol tI 46, space group I 4/ mmm ; a = 6.5312(2) Å, c = 22.2845(6) Å] was refined from single-crystal X-ray diffraction data. The phase was obtained after 10 d at 910 °C with small impurities of clathrate-I, BaGe 7 Ir 2 and α-Ge remaining at the grain boundaries. Ba 3 Ge 16 Ir 4 is a Pauli-paramagnetic metal, which becomes superconducting below T c = 5.1 K. Electronic structure and analysis of the chemical bonding were performed based on density functional theory calculations. The physical properties are discussed in comparison to the isotypic phase Ba 3 Ge 16 Rh 4 .

Description: Four zinc(II) complexes, namely, Zn(Hdmpz) 2 (L1) 2 ( 1 ) (Hdmpz = 3, 5-dimethylpyrazole, HL1 = trichloroacetic acid), Zn(Hdmpz) 2 (L2) 2 ( 2 ) (HL2 = 2, 4-dichlorophenoxyacetic acid), [Zn 2 (μ-dmpz) 2 (Hdmpz) 2 (L3) 2 ] ( 3 ) (HL3 = 1-naphthylacetic acid), and [Zn(Hdmpz) 2 (L4) 2 ] · H 2 O ( 4 ) (HL4 = indole-3-acetic acid) were prepared and structurally characterized by different techniques including elemental analysis, IR spectroscopy, TG, and single-crystal X-ray diffraction analysis. The complexes display 2D to 3D structures with tetrahedral to pentagonal coordination around the central zinc atom. The X-ray studies suggested that 1 , 2 , and 4 are mononuclear complexes, whereas 3 is a centrosymmetric dinuclear complex. The pyrazole ligand is coordinated in both terminal as well as a bridging fashion in the dinuclear moiety but the pyrazole ligand in the mononuclear complexes is coordinated only in monodentate terminal fashion with its neutral N group. The carboxylate groups behave as monodentate ligands in 1 – 3 , whereas the carboxylate in 4 functioned as both monodentate and chelating bidentate ligand. On the basis of X-ray crystallographic study the rich intra- and intermolecular weak interactions such as classical hydrogen bonds, C–H ··· O, CH 3 ··· O, CH–Cl, Cl–Cl, C–H ··· π, CH 2 –π, CH 3 –π, O–π, and π–π are analyzed. All these noncovalent interactions help to assemble the discrete complexes into high-dimensional ordered superamolecular structures.

Description: Acetate trinuclear metal complexes of Zn II and Co II with the potentially tridentate Schiff base ligand, having mixed phenolate, imine, and pyridine donor groups, HL, were synthesized. The complexes were characterized by microanalysis, LSI mass spectrometry, IR, UV/Vis spectroscopy, and magnetic measurements. Crystal structures of [ M 3 L 2 (OAc) 4 ] ( M = Zn II , Co II ) complexes, were also determined. The X-ray structures show the presence of trinuclear complexes with metal ions joined by phenolate and acetate bridging groups. The ligands coordinate to the metal ions through the imine nitrogen and their corresponding attached pyridyl and phenolate groups. The coordination environment for the metal ions is completed by bridging acetate anions to generate an octahedral coordination arrangement for the Co II complex and mixed distorted, bipyramidal trigonal and octahedral arrangements for the Zn II complex.

Description: Starting from a flexible tri-carboxylic acid ligand H 3 L {H 3 L = 2,4,6-tris[(4′-carboxyphenoxy)methyl]-1,3,5-trimethylbenzene}, a 3D metal-organic framework [Zn(HL)(H 2 O)] n ( 1 ) and a 2D polymeric layered solid {[(CH 3 ) 2 NH 2 )] 2 [Cd 2 L 2 (DMA) 2 ]} n ( 2 ) were hydrothermally synthesized. The complexes were characterized by elemental analyses, FT-IR spectroscopy, TGA, and single-crystal X-ray diffraction. The X-ray structural analyses reveal that the complex 1 is an example of a doubly interpenetrated 3D helical MOF with mutually entwined right- and left-handed helices to form an overall racemic framework. Complex 2 is made up of fourfold interwoven 2D nets in the solid state.

Description: Oxidovanadium(IV) complexes, [VO(acac)(L)Cl] ( 1 ), [VO(cur)(L)Cl] ( 2 ), and [VO(scur)(L)Cl] ( 3 ) {acac = acetylacetonate, cur = curcumin monoanion, scur = diglucosylcurcumin monoanion, L = 11-(9-acridinyl)dipyrido[3, 2-a:2',3'-c]phenazine (acdppz)}, were prepared and characterized. The complexes are non-electrolytic in DMF and 1:1 electrolytic in aqueous DMF. The one-electron paramagnetic complexes showed a d-d band near 725 nm in aqueous DMF and green emission near 520 nm in aqueous DMSO. The complexes exhibited an irreversible V IV /V III redox response near –0.85 V versus SCE in aqueous DMF. The complexes showed good binding strengths to calf thymus DNA ( K b : 3.1 × 10 5 –9.6 × 10 5 M –1 ) and efficient pUC19 DNA photocleavage activity in red light of 705 and 785 nm by singlet oxygen ( 1 O 2 ) pathway. Complexes 1 and 2 exhibited significant photocytotoxicity (IC 50 : 0.1–1.0 μM) in visible light (400–700 nm) with low dark toxicity (IC 50 : 〉20 μM) in HeLa and HaCaT cells. Complex 3 was cytotoxic in both light and dark. DNA ladder formation experiments indicated cell death via apoptotic pathway. Confocal microscopy done with 1 and 2 revealed primarily cytosolic localization of the complexes with significant presence of the complex in the mitochondria as evidenced from the imaging data using mitotracker red.

Description: The coordination polymer [Cd(HL)(BPDA)] n · n H 2 O ( 1 ) based on 3-(5-(pyridin-4-yl)-1 H -1,2,4-triazol-3-yl)pyridine (HL) and 1,1′-biphenyl-4,4′-dicarboxylic acid (H 2 BPDA) was hydrothermally synthesized and characterized by single-crystal X-ray diffraction, XRPD, IR spectroscopy, and elemental analysis. The asymmetric unit of compound 1 consists of one crystallographically independent Cd II ion, one HL ligand, “two half” BPDA 2– ligand, and one lattice water molecule. There are two crystallographically different BDPA 2– moieties, but each of them is placed in a symmetry element. The BPDA 2– ligands and Cd II ions connected to2D sheet, and the 2D sheets are connected to a 3D MOF by the HL ligands. Each dimeric Cd II unit links six nearest neighbors through the BPDA 2– and HL ligands, and the dimeric Cd II units are centrosymmetric. Two parallel HL ligands connect two dimeric Cd II units, generating long Cd2–HL–Cd2–HL rings, also centrosymmetric. So we can define the dimeric Cd II unit as a 6-connected node. Thus, the 3D structure can be described as a threefold parallel interpenetrated bsn beta-Sn topology. In addition, the optical properties of compound 1 and the free ligand H L were investigated.

Description: The 4-connected dmp -type cadmium(II)-isonicotinate framework [Cd(isonic) 2 (H 2 O)] n · n (DMA) ( 1 ) (isonic = isonicotinate, DMA = N , N ′-dimethylacetamide) was obtained by the solvothermal reactions of Cd(NO 3 ) 2 and isonicotinic acid (Hisonic). Compound 1 features a 3D porous framework with the opened channels occupied by the lattice DMA molecules. Thermal analysis reveals that such framework remains much stable after removal the free DMA molecules. CO 2 adsorption measurement shows that such framework exhibits notable CO 2 adsorption behavior.

Description: The reaction of the basic bismuth nitrate [Bi 6 O 4 (OH) 4 (NO 3 ) 6 ] · H 2 O with either thiosalicylic acid or sulfuric acid gave the novel bismuth hydrogen sulfate [Bi 2 (SO 4 ) 2 (dmso) 8 ](HSO 4 ) 2 ( 1 ) (DMSO = dimethyl sulfoxide). The formation of sulfate ions is observed in the presence of either Bi 3+ or [Bi 6 O 4 (OH) 4 ] 6+ indicating bismuth-induced oxidation of thiosalicylic acid. Compound 1 was characterized by elemental analysis, infrared spectroscopy, thermal analysis (TGA), and temperature dependent in situ X-ray powder diffraction. Crystals suitable for single crystal structure analysis were obtained from a DMSO/acetone solution. The title compound 1 crystallizes in the triclinic space group P with the following lattice parameters: a = 9.5240(4) Å, b = 9.9535(4) Å, c = 12.6620(5) Å, α = 109.943(4)°, β = 93.952(3)°, γ = 102.868(3)°, V = 1086.17(8) Å 3 , and Z = 1. Analysis of the thermally induced decomposition revealed the formation of Bi 2 O(SO 4 ) 2 and Bi 2 O 2 (SO 4 ) as intermediate products and Bi 28 O 32 (SO 4 ) 10 as final product.

Description: Recently, the synthesis of hexadentate ligands based on N , N ′-bis-(2,2′-bipyridine-6-ylmethyl)-2,2′-biphenylenediamine ( 1a – d ) and the corresponding iron(II) complexes ( 3a – d ) was reported by our group. In this contribution we present the synthesis of the analogous cobalt(II) complexes 4a – d . Together with the iron(II) complex the electrochemical behavior of the complexes 3 and 4 was investigated by cyclic voltammetry (CV). The aminomethyl substructure was identified as the main source of ligand degradation caused by chemical oxidation with air. Upon exposure to air the amine group in complexes 3 and 4 is oxidized to imine and even amide groups. Some examples ( 8 , 9 ) of the oxidation products were characterized by X-ray structure analysis. In order to increase the robustness of the Fe II and Co II complexes towards oxidation, the ligand scaffold of 1a was modified by N -methylation of the amino group yielding the tertiary amine 2 . The corresponding iron(II) and cobalt(II) complexes employing 2 as ligand were synthesized {[Fe( 2 )][PF 6 ] 2 ( 5 ), [Co( 2 )][PF 6 ] 2 ( 6 )} and fully characterized, their redox behavior and spin-state was investigated by CV and Evans' method. It was found, that the introduced N -methyl group leads to a substantial anodic shift of the M II – M III redox potential and the stabilization of Fe II and Co II high-spin state. By means of X-ray structure analysis these effects could be explained by repulsive steric effects of the methyl group.

Description: The intermetallic compounds Y 2 RuB 6 , Y 2 ReB 6 , Y 2 RhSi 3 , YRh 2 Si, and YPdSi were synthesized from the elements by arc-melting and subsequent annealing in sealed silica ampoules. The samples were studied by X-ray diffraction on powders. The structures of Y 2 RuB 6 and Y 2 RhSi 3 were refined from single crystal diffraction data: Y 2 ReB 6 type, Pbam , a = 916.3(2) pm, b = 1150.3(3) pm, c = 364.37(9) pm, wR 2 = 0.1056, 942 F 2 values, 38 variables for Y 2 RuB 6 and Er 2 RhSi 3 type, a = 812.6(2), c = 787.2(1) pm, wR 2 = 0.0682, 369 F 2 values, 17 variables for Y 2 RhSi 3 . The five compounds are characterized by two or three (YPdSi), crystallographically independent yttrium sites, which were all well resolved in 89 Y solid state NMR spectra. The NMR signal shifts were correlated with the density of states of the s electrons at the Fermi level, resulting in a non-ambiguous assignment of the NMR signals to the various sites in the crystal structures.

Description: The title complexes were obtained by reactions of [(η 5 -C 5 H 5 )(CO) 2 Fe] – , [(η 5 -C 5 H 4 CH 3 )(CO) 2 Fe] – , [Re(CO) 5 ] – , or [Mn(CO) 5 ] – with the mixed anhydride from the respective pyridine carboxylic acid and pivalic acid or with isonicotinic acid chloride, and were characterized by spectroscopic data and elemental analysis.

Description: The N -(2, 6-diisopropylphenyl)- N ′-benzoylthiourea ligand (shown as L ) ( 1 ) was synthesized and characterized. Reactions of 1 with CuCl 2 and CuBr 2 afforded the monomeric L 2 CuCl ( 2 ) and dimeric [ L BrCu(μ- L )] 2 ( 3 ), respectively, due to the reduction of Cu II . The reaction of 1 and CuCl gave the same product L 2 CuCl ( 2 ), while the treatment of 1 with CuBr led to the formation of a rare example of adamantanoid cage ( L Cu) 2 (μ- L ) 2 Cu 2 (μ-Br) 4 ( 4 ) containing enantiomeric couple. The product of 1 and CuI was found to be dimeric [ L ICu(μ- L )] 2 ( 5 ), which is isomorphous to 3 . All compounds obtained were fully characterized by elemental analysis, IR, 1 H NMR and 13 C NMR spectroscopy, and single-crystal X-ray diffraction.

Description: Thermodynamic data for gaseous SiF 2 and SiCl 2 known from literature show that these binary subhalides are formed nearly quantitatively at 1376 °C and 1076 °C, respectively, as products of the reaction of elemental silicon with SiF 4 or SiCl 4 at 1 × 10 –2 mbar. Applying the co-condensation technique SiF 2 as well as SiCl 2 can be trapped at –196 °C and prepared in synthetic scale. Herein, first analysis of metastable SiF 2 and SiCl 2 solutions are presented, showing that SiF 2 is more reactive than SiCl 2 leading to compounds of low boiling point of so far unknown composition. The metastable SiCl 2 solution can be used as a SiCl 2 source, which is shown by the trapping reaction with Idipp [Idipp = 1, 3-bis(2, 6- i Pr 2 -C 6 H 3 )imidazol-2-ylidene] leading to Idipp-SiCl 2 . The reactivity of the solution might be fine-tuned by changing the donor opening the door for further applications.

Description: Lithium transition metal silicates, Li 2 M SiO 4 ( M = Fe, Mn, Co), have attracted much interest as positive electrodes for Li-ion batteries due to their high theoretical capacities and their rich crystal chemistry. Low (β) and high (γ) temperature forms of these tetrahedral structures differ in the ordering/distribution of cations within tetrahedral sites of an hcp based packing of oxygen. We have carried out VT powder neutron and X-ray diffraction on Li 2 M SiO 4 ( M = Fe, Mn) to characterize the rich polymorphism observed across the Li 2 M SiO 4 ( M = Fe, Mn) system as a function of temperature. For Li 2 FeSiO 4 below 500 °C a β II phase was observed with slight Li/Fe disorder. Above this temperature there was a sluggish transition to the γ s phase, which was observed up to ca. 820 °C, with the γ II polymorph seen at highest temperatures. Excellent agreement with phases obtained by quenching was observed, except that the γ phases exhibit a statistical distribution of Li/Fe, in contrast to the well-ordered structures of quenched phases. The Li 2 MnSiO 4 polymorphism is less complex, the β II phase is stable from room temperature to 750 °C, at which temperature it transforms to the γ structure with disordered Li/Mn.

Description: Ag@Au core-shell nanoparticles were synthesized by using a fluorescent dipeptide β -Ala-Trp in water medium and at a room temperature without using any external reducing and stabilizing agents. The shell thickness of gold in core-shell Ag@Au nanoparticles has also been varied by changing the concentration of the gold(III) precursor keeping the other conditions same. The optical property of these core-shell nanoparticles varies with the shell thickness. Interestingly, these core-shell nanoparticles exhibit good catalytic property for the reduction of nitrophenols to aminophenols and nitroanilines to aminoanilines. A series of nitrophenol and nitroaniline compounds were taken as substrates for reduction. Moreover, this core-shell nanoparticle displays remarkable difference in catalytic property for reduction of nitro group with the variation of shell thickness. This catalyst (Ag@Au core-shell nanoparticle) can also be recycled for several times indicating its reusability.

Description: Two coordination polymers, namely {[Mn(2,4′-bpdc)(bimb)(H 2 O) 0.5 ] · 0.5H 2 O} n ( 1 ) and [Mn(4,4′-bpdc)(bimb)] n · 2.5H 2 O ( 2 ) [2,4′-bpdc = biphenyl-2,4′-dicarboxylate, 4,4′-bpdc = biphenyl-4,4′-dicarboxylate, and bimb = 1,4-bis(1-imidazol-yl)-2,5-dimethyl benzene], were hydrothermally synthesized by reactions of manganese(II) salt with the rigid ligand 1,4-bis(1-imidazol-yl)-2,5-dimethyl benzene and isomeric biphenyl dicarboxylate ligands. Complex 1 has an unusual 6-connected three-dimensional (3D) architecture with point symbol (4 4 .6 11 ). Complex 2 has also a 3D structure with two-interpenetrated pcu topology with point symbol (4 12 .6 3 ). Structural comparisons show that the positions of the carboxylate groups in the ligand backbone play an important role in governing the structural topologies of these complexes.

Description: The semirigid exo -bidentate ligand 1, 4-bis{[(2′-picolylaminoformyl)phenoxyl]methyl}-2, 5-bismethylbenzene (L) was designed, synthesized, and used as building blocks for constructing luminescent lanthanide polymers. Two new lanthanide coordination polymers were characterized by elemental analysis, X-ray diffraction analysis, and IR spectroscopy. The coordination polymers exhibit the metal-to-ligand molar ratio of 1:1 and the semirigid exo -bidentate ligand bridges lanthanide nitrates forming a zigzag chain, which further interconnected to three dimensional supramolecular structure in aid of cooperative C–H ··· O hydrogen bonds. The luminescence properties of the europium(III) complex are discussed in detail.

Description: The following study discusses the synthesis of macroporous glass beads, featuring variable pore sizes, and their application as starting material for a double templating route according to the nanocasting principle. In the first step, the initial porous glass was filled with the carbon precursor, a mesophase pitch, which after the subsequent carbonization and dissolution of the glass matrix results in an inverse macroporous carbon replica. Afterwards, the carbon beads were filled with amorphous silica by a typical sol-gel-process. The next step can be divided into two phases. The silica gel phase was first “structured” inside the macropores of the inverse carbon replica by converting it into an ordered mesoporous phase via pseudomorphic transformation. This process demanded alkaline conditions and a surfactant, that finally converts the silica into hierarchically structured beads with the dimension and the pores of the initial glass and MCM-41 pores inside the walls. The final step comprised the template removal via calcination. The obtained materials were characterized by mercury intrusion, nitrogen adsorption, scanning electron microscopy, x-ray powder diffraction and particle size analysis. In comparison to the previously reported approaches, the new method allows a higher flexibility in the texture properties of the resulting hierarchically structured materials including a variable ratio between ordered mesopores and additional macropores by parallel control of the total porosity and wall thickness in the starting porous glass.

Description: New periodic mesoporous organosilicas were synthesized using [bis(triethoxysilyl)vinyl]aniline (BTEVA) and [bis(triethoxysilyl)vinyl]benzene (BTEVB) as precursors and by functionalizing the BTEVA PMO with aminopropyl groups. All PMO materials showed a high degree of hexagonal order in the respective P-XRDs as well as high surface areas with narrow pore size distributions. The PMOs together with activated carbon were investigated with regards to their hexanal adsorption capacity in a gravimetric apparatus with an attached GC-MS. For the amine PMOs two different regions during adsorption were found. In the first region loadings in the range of 30 wt% were reached by a fast adsorption process. In the second region the loading reached 50 wt% but with slower kinetics. In desorption experiments up to 150 °C the loading decreased from 50 wt% to 30 wt%, where an equilibrium state was observed. With GC-MS and NMR the first region could be assigned to a chemisorption process, where the hexanal forms an imine group with the amine function in a Schiff base reaction. The subsequent second region can be assigned to weaker and thus reversible physisorption. The total capacity (first and second region) is substantially higher for the amine PMOs than for the activated carbon. Due to the chemical bonding in the chemisorption process, the desorption behavior is completely different: compared to the activated carbon the bonding of hexanal is much stronger for the amine PMOs.

Description: The cover picture shows a section of the crystal structure of the coordination polymer Cu 1.5 (H 3 N-(CH 2 ) 6 -NH 3 ) 0.5 [C 6 H 2 (COO) 4 ]·5H 2 O( 1 ), which features channel-like voids accommodating hexane-1,6-diammonium cations that compensate for the negative charge of the three-dimensional framework. A space-filling view of the framework is inserted. The compound can be dehydrated to a trihydrate and rehydrated to the starting composition retaining the crystal structure. Cu 2 (H 3 N-(CH 2 ) 6 -NH 3 ) 0.5 (OH)[C 6 H 2 (COO) 4 ]·3H 2 O ( 2 ) has a similar framework structure with channels of different dimensions accommodating hexane-1,6-diammonium cations as well. The different compounds have been obtained from aqueous solution by employing the same method, however, at different temperatures. More details are discussed in the article by R. Köferstein and C. Robl on page 310ff.

Description: Perovskite-type LaVO 2.78 N 0.10 powder was synthesized by thermal ammonolysis of the oxide precursor LaVO 4 . By X-ray, neutron, and electron diffraction an orthorhombic crystal structure with space group Pnma was identified. XANES spectra showed that the oxidation state of vanadium changes from 5+ in LaVO 4 to approximately 3+ in LaVO 2.78 N 0.10 . The temperature dependence of the electrical conductivity revealed an Arrhenius-type behavior with an activation energy of 0.103 eV in the temperature range of 119–302 K indicating that the conduction process is thermally activated band transition. Based on the positive Seebeck coefficient, holes were identified as the dominant charge carriers in the temperature range of 100–302 K. Both the Seebeck coefficient and the thermal conductivity showed an anomaly at 138 K, which is attributed to the Néel temperature for antiferromagnetic ordering according to magnetic susceptibility measurements.

Description: From the reaction of 2,3-dihydro-1,3,4,5-tetraisopropylimidazol-2-ylidene ( 4 ) (Carb) with iodine a compound of composition Carb · I 2 was obtained. Crystals were isolated from dichloromethane and the X-ray structure analysis revealed the presence of both Carb-I 2 ( 6 ) and [Carb–I 3 –Carb]I ( 7 ) moieties including disordered solvent according to the composition of {[Carb–I 3 –Carb]I · 2Carb-I 2 · 2CH 2 Cl 2 } ( 5 ).

Description: The isovalent substitution of strontium for barium in CaBaCo 4 O 7 destroys the ferrimagnetism in a striking way though it keeps the same orthorhombic crystal symmetry and cobalt valence as the parent phase. The gradual weakening of ferrimagnetism in CaBa 1– x Sr x Co 4 O 7 (0 〈 x ≤ 0.10) leaves place to magnetic frustration together with antiferrimagnetism. The phase separation that appears, due to the strong competition between long range ferrimagnetic ordering and magnetic frustration, is interpreted by local melting of charge ordering. The latter originates from local structural distortion around the Ba(Sr) site. The dynamic scaling theory, τ = τ 0 ( T f / T g – 1) – zv , suggests that the frustrated magnetic phase is cluster glass in nature with strongly interacting spins. This finding reveals that the orthorhombic symmetry in CaBaCo 4 O 7 is not a sufficient condition to manifest ferrimagnetic ordering.

Description: Three iron(II)-2-aminophenolate complexes [(L 1 )Fe II (4- t Bu-HAP)] ( 2 ), [(L 1 )Fe II (HAP)] ( 3 ), and [(L 1 )Fe II (4-NO 2 -HAP)] ( 4 ) [L 1 = tris(2-pyridylthio)methanido anion, 4- t Bu-HAP = 2-amino-4- tert -butylphenolate, HAP = 2-aminophenolate, and 4-NO 2 -HAP = 2-amino-4-nitrophenolate] were isolated and characterized to study their reactivity towards dioxygen. The complexes were synthesized from the iron(II)-acetonitrile complex [(L 1 )Fe II (CH 3 CN) 2 ] + ( 1 ) using substituted 2-aminophenolates. Single crystal structure of 4 reveals that the mononuclear central iron atom is coordinated by a tetradentate N 3 C ligand and a monoanionic bidentate 4-NO 2 -HAP giving rise to a distorted octahedral coordination arrangement. The six-coordinate iron(II) complexes, 2 and 4 , react with dioxygen to form the corresponding iron(III)-2-iminobenzosemiquinonato radical complexes, [(L 1 )Fe III (4- t Bu-ISQ)] + ( 2 Ox ) and [(L 1 )Fe III (4-NO 2 -ISQ)] ( 4 Ox ). Complex 3 , on the other hand, undergoes an oxidative C–S bond forming reaction between HAP and pyridine-2-thiolate (PyS) to afford [(L 1 )Fe III (ISQ′)] + ( 3 Ox ) [ISQ′ = 5-(2-thiopyridyl)-2-iminobenzosemiquinonato radical]. In each case, the reaction proceeds via a low-spin iron(III)-2-amidophenolate intermediate species. All the complexes exhibit strong iron–carbon bonding interaction. The bond parameters of the oxidized complexes, obtained from the single crystal structures, clearly establish the presence of ligand-centered radical.

Description: Two coordination compounds of the ligand tetrazolate-5-carboxylate (tzc) with zinc(II), namely, [Zn 2 (tzc) 2 (bpp)] ( 1 ) and [Zn 2 (tzc) 2 (bpea)] ( 2 ) [bpp = 1,3-bis(4-pyridyl)propane, bpea = 1,2-bis(4-pyridyl)ethane] were synthesized by hydrothermal methods involving the in situ generation of the ligand from sodium ethyl tetrazolate-5-carboxylate. Both compounds 1 and 2 exhibit a three-dimensional structure with 3,4-connected self-penetrating net topology in which two-dimensional Zn II -tzc layers are interlinked by the bpp or bpea spacers, with the tzc ligand being in the μ 3 -N1,O1:N4,O2:N2 coordination mode. The luminescence properties of 1 and 2 were also investigated.

Description: Soft metal-organic grafting of periodic mesoporous silica (PMS) has recently been demonstrated to give gadolinium-loaded nanostructured hybrid materials with interesting 1 H relaxometric properties. Here, the sterically demanding alkoxide and aryloxide complexes, [ Ln (OCH 2 CMe 3 ) 3 ] 4 and Ln (OC 6 H 3 t Bu 2 -2,6) 3 ( Ln = La, Gd), respectively, were grafted onto PMS materials MCM-41, SBA-15, and SBA-1. Support materials with distinct topology and pore diameters were utilized in order to direct the metal precursors towards the PMSs internal or external surfaces. All hybrid materials were examined by N 2 physisorption, Diffuse Reflectance Infrared Fourier Transform (DRIFT) and solid-state NMR spectroscopy, as well as elemental analysis. The characterization data demonstrated the successful silica attachment of the alk(aryl)oxide complexes via the surface silanol groups. Careful design of the hybrid materials based on findings in our previous studies resulted in Gd III loaded materials with particularly high 1 H longitudinal relaxivities at high magnetic field strength (400 MHz). The highest relaxivity of r 1 = 31 mM –1 s –1 was found for material [Gd(OCH 2 CMe 3 ) 3 ] 4 @SBA-1 showing no intrapore metal loading. This value is amongst the highest relaxivities reported for Gd III loaded mesoporous nanomaterials so far at such high field strength. The metal loading, localization of metal centers (directed by the topology of the PMS), and the particular properties of the metal-organic precursor are factors found to influence r 1 .

Description: Salts of cyano borates bear potential of forming coordination polymers with solvent-filled voids as a source for porous materials. Herein we describe the synthesis and properties of novel cyano borates Na[H–B(O–C 12 H 8 –CN) 3 ], Na[B(O–C 12 H 8 –CN) 4 ] (C 12 H 8 = biphenyl) and Na[B{O–C 6 H 3 –(CN) 2 } 4 ], as well as a new modification of Na[B(O–C 6 H 4 –CN) 4 ]. Crystal structures of the sodium borates and the starting materials HO–C 6 H 3 –(CN) 2 and HO–C 12 H 8 –CN (new modification) are discussed as well. Data of nitrogen sorption experiments revealed a notable surface area in solvent-free Na[H–B(O–C 12 H 8 –CN) 3 ].

Description: The hydrothermal reaction of Zn(NO 3 ) 2 · H 2 O and a linear 2, 2′-bis-trifluoromethyl-biphenyl-4, 4′-dicarboxylic acid ( H 2 L ) ligand with –CF 3 groups at each phenyl moiety of the biphenyl rings leads to the formation of a three-fold interpenetrated metal-organic framework (MOF), {[Zn 2.66 O 0.66 ( L ) 2 ] · 2H 2 O} n ( 1 ) at 180 °C. Single-crystal X-ray diffraction studies revealed that 1 is constructed from polynuclear clusters [Zn 4 O(COO) 6 ] as secondary building units (SBU). These SBU are connected through the L 2– to generate an overall three-dimensional structure with a 6-connected primitive cuboidal (α-Po) network. Thermogravimetric analyses and variable temperature powder X-ray diffraction measurements suggested that 1 is thermally stable. The porosity of 1 was estimated by N 2 , CO 2 , H 2 , and CH 4 at different temperatures. The framework showed high selectivity of CO 2 uptake over N 2 and CH 4 . Furthermore, solid-state photoluminescence studies were carried out for complex 1 upon excitation at 275 nm at room temperature.

Description: Two Ln III complexes based on a nitronyl nitroxide radical were synthesized and characterized structurally and magnetically: [ Ln (hfac) 3 [NITPh m -Cl] 2 ][0.5CH 3 (CH 2 ) 5 CH 3 ] [ Ln = Er ( 1 ), Nd ( 2 )] [hfac = hexafluoroacetylacetonate, NITPh m -Cl = 2-(3′-chlorophenyl)-4, 4,5, 5-tetramethylimidazoline-1-oxyl-3-oxide]. X-ray crystal structure analysis revealed that the two complexes have similar mononuclear tri-spin structures, in which the metal ions are octacoordinated by two radicals and three hfac molecules to form a slightly distorted dodecahedral arrangement. Each tri-spin unit connects through intermolecular hydrogen bonds, resulting in the formation of one-dimensional wave-like chain. Both of the complexes form a one-dimensional structure by intermolecular hydrogen bonds. Variable temperature magnetic susceptibility measurements studies revealed that there are antiferromagnetic interactions between the paramagnetic ions ( Ln III and radical).

Description: The solid solution Ba 1– x Rb x Fe 2 As 2 (0 ≤ x ≤ 1) was synthesized by solid state reactions and characterized by X-ray powder and single crystal diffraction. The compounds crystallize in the ThCr 2 Si 2 -type structure (space group I 4/ mmm ) and contain layers of edge-sharing FeAs 4/4 -tetrahedra without bonds between the layers. Rubidium substitution decreases the temperature of the structural phase transition in BaFe 2 As 2 ( I 4/ mmm → Fmmm ) until the orthorhombic distortion is completely suppressed at x = 0.33. Superconductivity already emerges at x = 0.15, reaches the highest critical temperature of 37.5 K close to x = 0.4 and exists up to x = 1. The T c ( x ) phase diagram of Ba 1– x Rb x Fe 2 As 2 is remarkably similar to those of Ba 1– x K x Fe 2 As 2 and Ba 1– x Na x Fe 2 As 2 in spite of opposing volume effects. The highest critical temperature coincides with an almost ideal As–Fe–As bond angle (109.5°) in the FeAs 4 -tetrahedra. The reduced critical temperatures T c / T c, max of the so far known hole-doped 122-type superconductors exhibit a generic behavior, where the highest transition temperatures occur near 0.19 holes per iron, which is comparable to the hole-doped copper-oxides, where the maximum is near 0.16 holes per copper. Such remarkably similar values in the two classes of high- T c superconductors may not be fortuitous, and suggest parallels of both systems concerning the unresolved mechanism of unconventional superconductivity.

Description: It is a formidable challenge to arrange tin nanoparticles in a porous matrix for the achievement of high specific capacity and current rate capability anode for lithium-ion batteries. This article discusses a simple and novel synthesis of arranging tin nanoparticles with carbon in a porous configuration for application as anode in lithium-ion batteries. Direct carbonization of synthesized three-dimensional Sn-based MOF: [K 2 Sn 2 (1,4-bdc) 3 ](H 2 O) ( 1 ) (bdc = benzenedicarboxylate) resulted in stabilization of tin nanoparticles in a porous carbon matrix (abbreviated as Sn@C). Sn@C exhibited remarkably high electrochemical lithium stability (tested over 100 charge and discharge cycles) and high specific capacities over a wide range of operating currents (0.2–5 Ag –1 ). The novel synthesis strategy to obtain Sn@C from a single precursor as discussed herein provides an optimal combination of particle size and dispersion for buffering severe volume changes due to Li-Sn alloying reaction and provides fast pathways for lithium and electron transport.

Description: Single crystals of Cu 3 TaSe 4 were obtained by chemical vapor transport with iodine as transport agent. Cu 3 TaSe 4 crystallizes in the sulvanite structure type with space group P 3 m and a = 5.6613(3) Å at room temperature. Structure refinements against single-crystal X-ray diffraction data result in a Cu–Se distance slightly longer than the Ta–Se distance, whereas previous Rietveld refinements obtained a Cu–Se distance shorter than the Ta–Se distance [G. E. Delgado et al., J. Alloys Comp. 2007 , 439 , 346]. The structural variations of sulvanite type compounds Cu 3 MX 4 ( M = V, Nb, Ta; X = S, Se, Te) are discussed in view of small distortions of Cu X 4 and MX 4 tetrahedra and the atomic valences.

Description: Three metal organic coordination compounds, namely, {[Cd 2 (L1) 4 ] 2 · 9H 2 O} n ( 1 ), {[Zn(L1) 2 · 2H 2 O] 2 · H 2 O} n ( 2 ), and [Cu(L2) 2 ] n ( 3 ), [L1 = 3-chloro-2-(5 H -tetrazol-5-yl)pyridine; L2 = 3-chloropicolinic acid], were hydrothermally synthesized, in which L1 and L2 were synthesized by in situ reactions. X-ray diffraction analyses revealed that the 2D layer of complex 1 is built from a dinuclear Cd II second building blocks, whereas complex 2 shows 0D structure, which is built based on two L1 ligands, one zinc ion, and two water molecules. 3 shows a 1D infinite rod-shaped chain. Additionally, the solid-state fluorescence properties for compound 1 and 2 are also presented.

Description: Four new hybrid fluoroferrates synthesized with 1,4-diazabicyclooctane ( dabco ) are discussed. They were obtained through the use of conventional solvothermal synthesis in Teflon vessels to explore the composition space diagram of the (Fe 2+ ,Fe 3+ )- dabco -HF aq . chemical system with ethanol or dimethylformamide as solvent. These Class I hybrid fluorides exhibit isolated hydrated and/or fluorinated iron entities associated to mono or diprotonated amines according to the synthesis conditions. Their structures were determined from single crystal diffraction: ( dabco H 2 )[Fe III 2 F 8 (H 2 O) 2 ] ( I ), triclinic, space group P , Z = 2, a = 7.1657(2) Å, b = 7.6031(2) Å, c = 13.1497(3) Å, α = 73.631(1)°, β = 76.210(1)°, γ = 84.286(1)°, V = 667.1(1) Å 3 , R = 0.0299; ( dabco H 2 ) 2 [Fe III 2 F 10 ] · 2H 2 O ( II ), orthorhombic, space group Pbca , Z = 4, a = 12.9801(7) Å, b = 11.4624(6) Å, c = 13.8641(7) Å, V = 2062.7(2) Å 3 , R = 0.0425; ( dabco H) 4 [Fe III 2 F 10 ] · 10H 2 O ( III ), triclinic, space group P , Z = 1, a = 8.921(3) Å, b = 9.468(4) Å, c = 13.452(4) Å, α = 76.87(2)°, β = 74.62(2)°, γ = 74.86(2)°, V = 1042.2(6) Å 3 , R = 0.0549; ( dabco H)[(Fe II (H 2 O) 6 )(Fe III F 6 )] ( IV ), trigonal, space group P 31 c , Z = 2, a = 9.2866(2) Å, c = 10.2401(2) Å, V = 764.8(3) Å 3 , R = 0.0252. The paper focuses on structural descriptions, environment of dabco cations or iron species, and hydrogen bonding modes in the light of literature examples.

Description: Undoped and doped CeO 2 nanoparticles were synthesized through a combination of microwave-assisted nonaqueous sol-gel route and thermal treatment at 300 °C. Nanocrystals of 3 nm were obtained and characterized in detail by Rietveld refinement analysis of the X-ray diffraction data and by electron microscopy. The refinement indicated that the doping with 3d transition metals (Co, Cu, Fe, and Ni) was successfully achieved and this result was additionally confirmed by EDX measurements. Investigation of the particle morphology by electron microscopy revealed that the nanocrystals were generally not present as primary particles, but self-assembled into often intergrown flakes with uniform diameters of about 150 nm. In selected cases, the ceria nanocrystals are crystallographically oriented with respect to each other within one flake. BET measurements revealed a high surface area of 126 m 2 · g –1 .

Description: Single phase cobalt disulfide (CoS 2 ) nanoparticles were prepared by thermal decomposition of cobalt-thiourea complex at a low temperature (400 °C). CoS 2 nanoparticles exhibit ferromagnetic ordering at 122 K below which the temperature dependent resistivity of cold pressed nanoparticles deviates from metallic behavior and shows a broad maximum. Just below T C , it also exhibits a large magnetoresistance effect (6.5 %). A mixture of CoS and Co 9 S 8 phases were obtained between the temperature interval 400 °C 〈 T 〈 1000 °C. At 1000 °C, a pure bulk Co 9 S 8 phase was obtained. It exhibits magnetic hysteresis typical of a ferromagnet at room temperature and a peak in magnetization at low temperature with a strong relaxation indicating possible spin glass state.

Description: An ionic liquid assisted strategy for the synthesis of zeolitic material is reported. This strategy is a solid state synthetic method and the ionic liquid is employed as structure directing agent. A TON-type zeolite, which contains one-dimensional 10-member-ring, is successfully synthesized with the assistance of the ionic liquid, 1-ethyl-3-methylimidazolium bromide. This finding improves our understanding about the challenge of ionothermally synthesizing siliceous and aluminosilicate zeolites.

Description: Primary explosives, unlike secondary explosives, show a very rapid transition from combustion (or deflagration) to detonation and are considerably sensitive to small stimuli, such as impact, friction, electrostatic discharge, and heat. Primary explosives generate either a large amount of heat or a shockwave, which makes the transfer of the detonation to a less sensitive propellant or secondary explosive possible. 1 Primary explosives are key components in detonators and primers, which are the initiating elements to many military items such as small, medium, and large caliber munitions, mortars, artillery, warheads, etc. The two most common military primary explosives are lead azide and lead styphnate. Lead based compounds such as these have well-established hazards to health and the environment. To overcome these concerns, in common U.S. Army detonators and primers lead azide was replaced with DBX-1 [copper(I) nitrotetrazolate], recently developed by Pacific Scientific Energetic Materials Company and the U.S. Naval Surface Warfare Center at Indian Head. Further, in order to minimize the dangers to personnel and equipment associated with synthesizing and handling primary explosives, a dedicated, remote-operated facility for the synthesis and testing of primary explosives has been developed.

Description: Five mixed-linkers based coordination polymers, namely { M (1, 3-Hadc)(bpy)(H 2 O) 2 } n [ M = Ni II ( 1 ), Co II ( 2 )], {Zn(1, 3-adc)(bpy) 0.5 } n ( 3 ), {Cd(1, 3-Hadc) 2 (bpy)} n ( 4 ), and {Cu(1, 3-Hadc) 2 (bpp)} n ( 5 ) [1, 3-H 2 adc = 1, 3-adamantanediacetic acid, bpy = 4, 4′-bipyridine, bpp = 1, 3-bis(4-pyridyl)propane] were synthesized by solvent diffusion reactions. Their structures were determined by single-crystal X-ray diffraction analyses. Compounds 1 and 2 are isostructural and they have 1D linear coordination polymer structure that are further interdigitated via hydrogen bonding resulting in 2D extended networks. The dehydrated 1 shows type-I profile for H 2 O vapor suggesting hydrophilic nature of the framework. In compound 3 , a paddle-wheel type secondary building unit (SBU) directs the overall structure to form a 2D square grid type structure. The 2D sheets further stack along the c axis in a AB fashion and leaves no void space. Compound 4 has a hexacoordinate Cd II and forms a zigzag coordination polymer chain-like structure and these chains form a 2D structure by hydrogen bonding interactions. Compound 5 contains a longer linker bpp compared to bpy and forms a 2D structure similar to that of 4 . These results demonstrate that by changing the metal ions coordination mode versatile structures with different dimensionalities and network topologies can be realized in a same mixed linkers system.

Description: Cs 2 Ga 2 Se 5 was obtained by the reaction of CsN 3 with stoichiometric amounts of GaSe and Se at elevated temperature. It forms yellow crystals embedded in a pure orange microcrystalline powder. The crystal structure of Cs 2 Ga 2 Se 5 was determined by single-crystal X-ray diffraction at 123 K. The compound crystallizes monoclinically in the space group C 2/ c (No. 15) with a = 15.3911(5) Å, b = 7.3577(2) Å, c = 12.9219(3) Å, β = 126.395(3)°, V = 1177.89(7) Å 3 , and Z = 4. The structure features one-dimensional chains 1 ∞ [Ga 2 Se 3 (Se 2 ) 2– ], consisting of edge- and corner sharing GaSe 4 tetrahedra. Raman spectroscopic measurements reveal vibrational bands of the Se 2 2– units at 236 cm –1 , and the bands of Ga–Se vibrations at 254 and 273 cm –1 . UV/Vis diffuse reflectance spectroscopy shows the bandgap at about 1.95 eV.

Description: Two complexes with formulas [Ni(bpndc)(bpe)] n · 4 n H 2 O ( 1 ) and [Co(bpndc) (bpy) 1.5 ] n · 0.25 n (bpy) · 0.25 n H 2 O ( 2 ) (H 2 bpndc = benzophenone-4,4′-dicarboxylic acid, bpe = 4,4′-bipyridinediethene, bpy = 4,4′-bipyridine) were synthesized and characterized. In complex 1 , each bpndc ligands adopt bis(monodentate) modes, and Ni II ions are bridged by bpndc and bpe ligands into a 3D CdSO 4 -like porous metal-organic framework with channels. But triple interpenetration occurs. In complex 2 , each bpndc ligands adopt tridentate modes, and Co II ions are linked by bpndc and bpy ligands into 2D bilayer structures with the Schläfli symbol of (4 8 .6 2 ). Each bilayer is bicatenated in a parallel fashion by two other bilayers, which results in the formation of a 2D→3D polycatenation network.

Description: The reaction of selenium and NbCl 5 with arsenic in the Lewis-acidic ionic liquid BMImCl · 4.8AlCl 3 at 100 °C yielded dark-red block-shaped crystals of Nb 2 Se 4 (AlCl 4 ) 4 , which immediately decompose when exposed to humid air. Arsenic takes the part of the reducing agent for niobium as well as selenium. The crystal structure was described in the monoclinic space group P 2 1 / n (no. 14) with a = 898.0(1) pm, b = 991.3(1) pm, c = 1629.1(2) pm, and β = 92.43(1)° at 296(1) K. The unit cell contains two C 2h symmetric Nb 2 (Se 2 ) 2 (AlCl 4 ) 4 molecules. The latter consist of a central rectangular bipyramid [Nb 2 (Se 2 ) 2 ] 4+ and four η 2 -coordinating AlCl 4 – tetrahedra. Diamagentism of the compound and DFT-based real-space bonding analysis imply a chemical bond between the niobium(IV) cations, which are 292.2(2) pm apart. Nb 2 Se 4 (AlCl 4 ) 4 can be interpreted as the AlCl 3 adduct of NbSe 2 Cl 2 .

Description: The synthesis and structural characterization of two new homo- and heteroleptic tetravalent cerium complexes with tert -butoxo and heteroarylalkenolate ligands of the general formula [Ce(O t Bu) 2– x L x +2 ] [ x = 2 ( 1 ), x = 0 ( 2 )] [ L = Dmox-CHC(CF 3 )O] is described. Their thermal decomposition behavior as well as their potential as single-source precursor for the fabrication of nanostructured ceria was evaluated. By using the heteroleptic alkoxide complex 2 as metal organic precursor, an efficient synthesis of highly crystalline CeO 2 QDs with a narrow size distribution was achieved by microwave assisted solvothermal synthesis in NMP. It was found that an expedient choice of precursor enabled the replacement of additives like bases or other mineralizer and opens an efficient pathway for controlled nucleation of metal oxide nanoparticles.

Description: We report on the synthesis and application of a 2 nm long, curved ditopic biscarboxylic ligand with a 1,4-bis(ethynyl)bicyclo[2.2.2]octane rotator core and an helical twist to the construction of an extended single-crystalline framework solid with paddlewheel hinges, [Cu II ] 2 [1,4-bis(carboxyphenyl ethynyl)bicyclo[2.2.2]octane] 2 (H 2 O) 2 or [Cu II ] 2 (bbcbco) 2 (H 2 O) 2 . The interconnection of interpenetrated square lattices involves short rotor–rotor H ··· H interactions (1.9 to 2.4 Å) such that the moving parts are expected to rub onto each other in the lattice in a Brownian rotational motion with a calculated rotational barrier of 3.7 kcal · mol –1 . Variable-temperature 1 H spin-lattice relaxation ( T 1 ) experiments carried out on a static crystalline sample did not provide however a value of this rotational barrier because the relaxation proved to be dominated by the coupling of the moving protons to the electronic spins of the Cu II dimers. Remarkably, we reveal how the singlet-triplet spin dynamics of non-interacting Cu II dimers is elegantly characterized by solid state NMR spectroscopic experiments yielding an exchange coupling constant, J exp = –365 K = –254 cm –1 , in good agreement with theoretical estimations and experimental data on related Cu II dimer systems.

Description: Six isomorphous metal-organic frameworks: Ln 2 (bpdc) 3 (tptz) 2 (H 2 O) · 3DMA · 7H 2 O [ Ln 3+ = Nd 3+ ( 1 ), Sm 3+ ( 2 ), Eu 3+ ( 3 ), Gd 3+ ( 4 ), Tb 3+ ( 5 ), Dy 3+ ( 6 )] [bpdc 2– = 4,4′-biphenyldicarboxylate, tptz = 2,4,6-tris(2-pyridyl)-1,3,5-triazine, DMA = N , N -dimethylacetamide], were synthesized by the self-assembly of lanthanide ions, bpdc 2– , tptz, DMA, and H 2 O. Single-crystal X-ray diffraction reveals that all compounds are 1D coordination polymers with π–π interactions via tptz among adjacent chains, forming a 3D supramolecular network. Compounds 2 , 5 , and 6 exhibit mainly ligand luminescence, whereas 3 exhibits intense characteristic Eu 3+ emissions at room temperature.

Description: A congruent melting compound MgSrB 2 O 5 was synthesized by high temperature solution method from the MgO-SrO-B 2 O 3 system, and the structure was determined by single-crystal X-ray diffraction methods. The compound crystallizes in the monoclinic system, with space group P 2 1 / c . The crystal structure is composed of isolated B 2 O 5 units and MgO 6 octahedra that are connected to form two-dimensional [Mg 2 B 4 O 10 ] layers stacking along the c axis. The layers are bridged by the Sr 2+ cations to form a three-dimensional framework. The IR spectrum and the thermal properties of MgSrB 2 O 5 were also reported. Additionally, detailed structure comparisons between MgSrB 2 O 5 and other borates, such as Mg 2 B 2 O 5 , Sr 2 B 2 O 5 and SrCdB 2 O 5 are carried out and the first-principle theoretical studies are performed to aid the understanding of electronic structures and linear optical properties.

Description: A series of new gallium-containing silicotungstates was obtained from the one step reaction of the lacunary Na 10 [α-SiW 9 O 34 ] · 15H 2 O Keggin-type building block ( SiW 9 ) with gallium nitrate in aqueous solution. The sandwich-type polyoxotungstate [Ga 6 (H 2 O) x {α-SiW 9 O 34 (OH) y } 2 ] n – ( 1 ) crystallizes first as a mixture of two similar polyoxometalates ( 1a and 1b ), while [Ga 4 (H 2 O) 2 {α-SiW 10 O 38 } 2 ] 12– ( 2 ) is generated from the mother liquor in a second step. Both newly obtained polyoxometalates with tetra- and hexanuclear gallium cores were structurally characterized with a wide range of methods encompassing single crystal and powder X-ray diffraction techniques, FT-IR spectroscopy, and thermal analysis. The solution stability of both dimeric POMs K 10 [Ga 6 (H 2 O) 3 {α-SiW 9 O 35 (OH) 2 } 2 ] · 35.5H 2 O ( 1a ) and K 12 [Ga 4 (H 2 O) 2 {α-SiW 10 O 38 } 2 ] · 30H 2 O ( 2 ) was investigated with 183 W NMR and HR ESI mass spectrometry, and the electrochemical properties of both compounds were determined by cyclic voltammetry.

Description: Reaction of the rigid ligand 2,4,5,6-tetrachloro-1,3-benzenedicarboxylic acid (1,3-H 2 BDC-Cl 4 ) with copper(II) nitrate in different solvent systems afforded two new complexes {[Cu(1,3-BDC-Cl 4 )(DMF)] (H 2 O)} n ( 1 ) and {[Cu(1,3-BDC-Cl 4 )(H 2 O) 3 ] (dioxane) · (H 2 O)} n ( 2 ), which were fully characterized by elemental analysis, IR spectroscopy, as well as single crystal and powder X-ray diffiraction techniques. Single-crystal X-ray diffraction reveals that complexes 1 and 2 crystallize in different space groups P 2 1 / m and Pbca , respectivly. Compound 1 shows a two-dimensional (2D) (4,6)-connected layered network constructed by the connectivity between one-dimensional (1D) [–Cu–DMF–COO–] n chains and tetrachlorinated backbones of 1,3-BDC-Cl 4 , which is further assembled to generate a three-dimensional (3D) supramolecular framework through intermolecular O–H ··· O and O–H ··· Cl hydrogen-bonding interactions. Compound 2 features a 2D 4-connected sql coordination net formed by 1D [Cu-H 2 O] n chains and 1,3-BDC-Cl 4 spacers, which is further extended into a 3D supramolecular network by multiple O–H ··· O hydrogen-bonding interactions. The different structural features of the two compounds suggest that the choice of solvent systems should play a key role in the process of assembly. Their thermal and fluorescence properties were also investigated.

Description: The effect of oxygen substitution at the selenium site and manganese substitution at the iron site in FeTe 0.5 Se 0.5 superconductor was investigated. It was found that upon partial O substitution, T c marginally decreases as seen in both resistivity and magnetization experiments. T c decreases even by a small amount of oxygen concentration (as low as 1 %). This observation is in contrast against an earlier work on Fe(Te/Se) samples, 1 wherein T c as well as superconducting volume fraction were reported to increase in the samples annealed in air . Mn-doping leads to a decrease in T c in FeTe 0.5 Se 0.5 , which one would expect considering pair-breaking due to Mn 2+ -ions.

Description: The two dimensional Mn II coordination polymer [Mn 3 (pic) 2 (N 3 ) 4 (CH 3 OH)] n ( 1 ) with the ligands azide and picolinic acid (Hpic) was synthesized and characterized by IR spectroscopy, elemental analysis, and powder and single-crystal X-ray diffraction analysis. Meanwhile, analysis of the magnetic properties revealed antiferromagnetic exchange for polymer 1 .

Description: A method for converting natural Jordanian kaolin without thermal pre-activation into a synthetic zeolitic molecular sieve, known as zeolite A, is presented. All previous efforts to convert the kaolin into zeolite A have involved the use of high temperature or expensive minerals or organic acids. Natural Jordanian kaolin and citric acid were used under these conditions for the first time and reaction parameters were optimized. In this approach, an optimized low temperature zeolite synthesis process is performed for production of zeolite A of suitable quality at interesting commercial conditions. The process comprises direct alkaline conversion of natural kaolin into hydroxysodalite, subsequent to dissolving the hydroxysodalite in a dilute acid, prior to crystallization of zeolite by adding alkali hydroxide. After sodalite formation, aqueous base is added to the whole slurry until the pH exceeds 12 and a zeolite precursor gel is formed. The resulting precursor gel is aged for 4 h at a temperature of 100 °C to form a zeolite of type A. Zeolite made in accordance with the presented approach may be used as chemicals, molecular sieves, and catalyst. The obtained products were characterized with powder X-ray diffraction, Fourier transform Infrared spectroscopy, scanning electron microscopy, differential thermal analysis, and thermogravimetric analysis. The results showed that zeolite A is formed together with residual amorphous silica resulting from the quartz fraction in the kaolin. The morphology of the obtained zeolite A could be seen as well crystallized with cube shape.

Description: The cover picture shows the group-subgroup relation for the stannides AuSn and AuNiSn 2 in the compact and concise Bärnighausen formalism. The coloring of the gold and nickel atoms on the transition metal sites of the nickel arsenide subcell proceeds in an ordered manner. Many other complex intermetallic compounds form superstructures that derive from simple subcells (e. g. CuAu, Cu 3 Au, MoNi 4 , ZrAl 3 , FeAl, or MoSi 2 ) through coloring, puckering, or distortions. The group-subgroup schemes facilitate structure systemization and help for the understanding of twinning problems. More details are discussed in the article by R. Pöttgen on page 869ff.

Description: A series of complexes of the new N 4 chelate ligand L (L = 1-{6-[1, 1-bis(pyridin-2-yl)ethyl]pyridin-2-yl}- N , N -dimethylmethanamine) with intermediate to late divalent transition metal ions M was obtained by the reaction between L and the respective chloride salt or similar precursor in methanol: [ M Cl 2 L] ( M = Mn, Fe, Co, Ni, Zn; Ru) and [CuClL]Cl. The stereochemical characteristics of the chelate ligand were studied by means of single-crystal X-ray diffraction, and quantified on the basis of several geometric parameters, including the tetragonal distortion Σ and the continuous symmetry measure S ( O h ). The overall distortion of the coordination environment is predominantly determined by the steric demand of the central ion, while electronic or other subtler influences essentially contribute to the distortion of the ligand L. Unlike similar complexes, [Mn II Cl 2 L] cannot be oxidized to a manganese(III) complex by dioxygen, hydrogen peroxide, or iodosylbenzene. In [Ru II Cl 2 L], one chlorido ligand can be exchanged against small π-accepting molecules such as acetonitrile or dinitrogen. L offers an environment ideal for small metal ions (0.4–0.6 Å), such as low-spin iron(II), which rationalizes the late onset of thermal spin crossover in the complex [Fe II L(NCS) 2 ].

Description: A number of aminosilanes derived from N -methylaniline and chloroorganylsilanes were prepared and characterized. X-ray structure analysis was performed on the crystalline derivatives Ph(Cl)Si(NMePh) 2 ( 4a ), HSi(NMePh) 3 ( 2b ), MeSi(NMePh) 3 ( 3b ), and Ph 2 Si(NMePh) 2 ( 6b ). The compounds were comprehensively characterized by 1 H, 13 C, 29 Si NMR, and IR spectroscopy. Volatile derivatives were further characterized by GC/MS. It was shown using quantum chemical methods that the planarization of the nitrogen atoms in the amino derivatives is caused by phenyl groups and silyl substituents.

Description: New modifications (denoted as β -) of the compounds H 2 SeO 3 , NaHSeO 4 , and Na 5 H 3 (SeO 4 ) 4 (H 2 O) 2 were isolated from aqueous solutions and their crystal structures determined from single crystal data. β -H 2 SeO 3 crystallizes in the space group P 1 with lattice parameters of a = 4.6794(4) Å, b = 5.0988(4) Å, c = 5.7743(5) Å, α = 102.252(6)°, β = 91.594(6)°, γ = 98.054(6)°, and consists of two unique trigonal-pyramidal SeO(OH) 2 units that are held together by O–H ··· O hydrogen bonds. β -NaHSeO 4 crystallizes in the space group P with lattice parameters of a = 5.0814(2) Å, b = 5.6345(3) Å, c = 6.5125(3) Å, α = 88.352(3)°, β = 73.163(3)°, γ = 82.027(3)°, and is made up of distorted NaO 6 octahedra and tetrahedral SeO 3 (OH) – anions, with the hydrogen atom statistically disordered between two positions. β -Na 5 H 3 (SeO 4 ) 4 (H 2 O) 2 crystallizes in the space group I 2/ c with lattice parameters of a = 7.0472(15) Å, b = 13.194(3) Å, c = 17.845(4) Å, β = 101.345(9)°. The asymmetric unit contains three Na + sites (one situated on a twofold rotation axis and each with a distorted octahedral coordination by oxygen atoms), one water molecule, one SeO 3 (OH) – anion, and half of an [SeO 4 ··· H ··· O 4 Se] unit with a very short interpolyhedral O ··· O distance of 2.447 (4) Å. The crystal structures of the β -modifications are comparatively discussed with those of the corresponding known α -modifications. Moreover, the crystal structure of Te 2 O 4 (OH) 2 was reinvestigated [ Pna 2 1 , a = 12.0512(8) Å, b = 8.0267(5) Å, c = 4.7268(3) Å], allowing the localization of the hydrogen atoms and hence a more detailed view of the hydrogen bonding system.

Description: We report a detailed investigation of the charge carrier transport in polycrystalline n -type impurity-doped zinc oxide (ZnO) thin films grown by spray pyrolysis over a wide range of carrier concentrations. Particular attention is devoted to a study of the composition-dependent metal-insulator transition (MIT) in this transparent conducting oxide (TCO). In order to describe the flow of electrons in these impurity-doped thin films over this full range of conditions, it is necessary to consider multiple electronic conduction processes. The first conduction process arises from current carriers thermally excited from impurity states into the (host) ZnO conduction band. The second involves thermally-activated, quantum-mechanical tunnelling within an impurity band located close to the host conduction band. The latter conduction process predominates at low temperatures whilst the former dominates at high temperatures. We find that a MIT occurs at a critical carrier concentration between 2 and 6 × 10 19 cm –3 . At higher concentrations in this metallic regime, the impurity band merges with the ZnO conduction band. The location of the MIT was determined from low temperature resistivity data and the results are discussed in terms of the Mott and Ioffe-Regel models. In addition, the overriding importance of grain boundaries is highlighted for these polycrystalline thin films; this is a key factor in determining and limiting electronic conduction in these samples, particularly at high temperatures. These results highlight the practical importance of understanding both the MIT and also grain boundary effects in determining the electrical performance of polycrystalline TCO films.

Description: The hydrothermal crystallization of SAPO-5 molecular sieves with Si mole ratios in the range of 0.05 to 0.13 was performed by either conventional or microwave heating to compare the influence of these two techniques on the isomorphous substitution of phosphorus by silicon atoms in the aluminophosphate framework. An extensive characterization of the obtained silicoaluminophosphates by ICP-OES, SEM, XRD, TPDA, and MAS NMR spectroscopy indicated that conventional heating (drying oven) led to a better crystallinity and a higher content of isolated framework silicon atoms than microwave heating. While microwave heating has the advantage of reducing the crystallization time and conventionally prepared SAPO-5 materials show better incorporation of isolated silicon atoms into the AFI framework according to the substitution mechanism SM IIa. This lower SM IIa substitution of tetrahedral framework sites by isolated silicon atoms in microwave-prepared SAPO-5 materials is the reason for their lower density of Brønsted acidic bridging OH groups [Si(OH)Al]. In contrast, the density of defect OH groups, such as weakly acidic SiOH groups, is higher than for conventionally prepared samples.

Description: Interaction of an alpha particle with triaminotrinitrobenzene (TATB) which is an insensitive explosive has been investigated by density functional calculations. It has been found that α-particles interact with TATB disturbing its planar geometry. As a result, the C–NO 2 bond dissociation energies are substantially decreased, whereas detonation velocity and pressure values increased as compared to TATB. The quantum chemical properties of the structures are presented.

Description: The intermetallic zinc compounds RE 6 Pd 13 Zn 4 ( RE = La – Nd, Sm, Gd, Tb) were synthesized from the elements in sealed niobium ampoules. They crystallize with the cubic Na 16 Ba 6 N (Dy 6 Fe 16 O) type structure, space group Im m . The samples were investigated by powder X-ray diffraction and four structures were refined on the basis of single-crystal X-ray diffraction data. The striking structural motifs are palladium centered RE 6 octahedra in a bcc arrangement. These octahedra are surrounded by a [Pd 12 Zn 4 ] network. Magnetic susceptibility studies of Gd 6 Pd 13 Zn 4 show Curie-Weiss behavior and an experimental magnetic moment of 7.75(2) μ B per Gd atom. Gd 6 Pd 13 Zn 4 orders antiferromagnetically at T N = 10.5(1) K.

Description: The new compound Fe 11 (TeO 3 ) 2 (TeO 4 ) 3 (PO 4 ) 2 O 4 Cl 3 containing Fe III and Te IV crystallizes in the monoclinic space group C 2/ c with the unit cell parameters a = 20.5816(5) Å, b = 26.7506(6) Å, c = 5.03910(10) Å, β = 93.587(2) o , Z = 4. Single crystals were grown in sealed and evacuated silica tubes at 550 °C. The compound exhibits an open framework structure built from [FeO 6 ], [FeO 5 Cl], [FeO 4 Cl], [PO 4 ], [TeO 3 ], and [TeO 4 ] polyhedra. The Te IV atoms adopt a one sided asymmetric coordination due to the stereochemically active lone-pair. The lone-pairs together with the chloride ions are excluded from the covalently bonded space and protrude into cavities extending along [001]. Bond valence sum calculations confirm iron to be in its Fe III state and the chloride ions to be underbonded and act more as counterions than being fully integrated in the covalent network.

Description: The control of the spin orientation transitions in perovskites containing manganese, cobalt, iron, and chromium, based on crystal chemistry factors is reviewed. We describe herein the effect of the size and of the magnetic nature of the Ln 3+ cations and of the doping and large substitutions at the octahedral sites. Spin blockade introduced by nanostructural effects and magnetic anisotropy induced by laser pulse application are also discussed.

Description: In Bragg–Brentano powder X-ray diffraction, incompletely filled sample holders result in a significant loss of intensity for diffraction peaks at small 2θ angles due to shadowing of the diffracted beam by the sample holder. This has to be considered in crystal structure refinements for samples with diffraction peaks in the low 2θ range when shifts of sample height cannot be avoided. Herein a geometrically derived correction algorithm to account for the intensity loss as a function of shift in sample height is presented. The algorithms were verified based on a series of zeolite A diffraction patterns from samples with deliberately induced, well defined reductions in sample height.

Description: The 6-layered hexagonal polymorph of BaCrO 3 has been synthesized at 900 °C under a pressure of 9 GPa. The hexagonal structure (space group P 6 3 / mmc , cell parameters a = 5.3809(9) and c = 13.123(3) Å at 300 K) is stable on cooling down to 5 K. Ferrimagnetism with a small saturated magnetization of approx. 0.1 μ B is observed below a Curie transition at T C = 192 K, and neutron diffraction shows that a simple collinear ferrimagnetic spin structure with moments parallel to c is adopted.

Description: Aiming at both high energy and power density, asymmetric supercapacitors with screen printed lithium cobalt oxide (LiCoO 2 ) and graphene oxide GO as electrode materials were assembled. LiCoO 2 was synthesized by a facile and inexpensive hydrothermal method, whereas GO was synthesized according to a modified Hummer's method. Both powders were coated on flexible stainless steel substrates using screen printing technology. Finally, asymmetric supercapacitors were assembled using LiCoO 2 as positive and GO as negative electrode with a porous polypropylene sheet as separator and an aqueous electrolyte solution of LiClO 4 . The electrochemical properties of this asymmetric cell were investigated by cyclic voltammetry and galvanostatic charge/discharge experiments. The asymmetric supercapacitor LiCoO 2 //GO could be cycled reversibly in the wide voltage region 0–1.5 V; it shows an impressive performance with an energy density of 19.2 Whkg –1 (based on the total mass of the active materials of the two electrodes). Importantly, this device exhibits an excellent long cycling life with 85 % specific capacitance retained after 1500 cycles. A demonstration cell could effectively light up an LED.

Description: Two new compounds with Co-centered Sn 9 clusters were obtained by the extraction directly from the intermetallic precursor K 4.79 Co 0.79 Sn 9 in ethylenediamine with addition of cryptand [2.2.2]. The anions [Co 0.68 @Sn 9 ] 4– in K[K([2.2.2]crypt)] 3 [Co 0.68 @Sn 9 ] ( 1 ) consisting of overlaying [Co@Sn 9 ] 4– and [Sn 9 ] 4– cluster anions are connected by K atoms to form infinite K[Co 0.68 @Sn 9 ] chains. The anions [Co 2 @Sn 17 ] 5– in [K([2.2.2]crypt)] 5 [Co 2 @Sn 17 ] · en · tol ( 2 ) are built from two [Co@Sn 9 ] sharing one common Sn atom, with the same composition but a different conformation as in the previously reported [K([2.2.2]crypt)] 5 [Co 2 @Sn 17 ]. Quantum chemical calculations for the different conformers of [Co 2 @Sn 17 ] 5– reveal that both conformers are rather close in energy and that the short intercluster Sn–Sn distance in 2 does not originate from attractive interactions.

Description: Treatment of the cluster compounds [Cp 2 (CO) 4 Mo 2 E SbCl] ( E = S, Se) with GaCl 3 in thf as solvent leads to the compounds [Cp 2 (CO) 4 Mo 2 E Sb]GaCl 4 . [Cp 2 (CO) 4 Mo 2 SSb]GaCl 4 crystallizes in the monoclinic system, space group P 2 1 /c with a = 815.64(6), b = 1094.31(5), c = 2503.7(2) pm, and β = 92.505(6)°. The selenium derivative [Cp 2 (CO) 4 Mo 2 SeSb]GaCl 4 forms isotypic crystals with a = 811.53(4), b = 1103.90(6), c = 2511.2(1) pm, and β = 92.704(4)°. Both the derivatives display ionic structures consisting of separated [Cp 2 (CO) 4 Mo 2 E Sb] + cations and GaCl 4 – anions. According to the 18 electron rule the [Cp 2 (CO) 4 Mo 2 E Sb] + cations can be considered as electron precise tetrahedral clusters, which are closely related to the well-known dipnictogen complexes [Cp 2 (CO) 4 Mo 2 E 2 ] ( E = P, As, Sb, Bi).

Description: The synthesis of NH 3 from N 2 and H 2 employing molecular ruthenium pincer complexes as catalysts was investigated by DFT calculations for an hitherto unusual type of outer sphere mechanism in N 2 chemistry. The mechanistic approach relies on the heterolytic cleavage of a H 2 molecule between the sterically demanding P( t Bu) 3 as a Lewis base and the dicationic ruthenium pincer complex [Ru(PNP)(N 2 )(CO) 2 ] 2+ [PNP = 2,6-bis(diisopropylphosphanyl)lutidin] as a Lewis acid. Cleavage of the H 2 molecule results in a hydride, which is transferred onto the external N atom of the N 2 molecule coordinated at the metal complex, while the proton binds to the base. In a subsequent step the proton is also transferred to the HNN unit. Repetition of these two reaction steps with two more H 2 molecules results in the formation of two NH 3 molecules. Closed catalytic cycles could be calculated, which proves that this concept is applicable in principle. However, some activation barriers in the middle stages of the catalytic cycle are too high to envision practical realization with this particular acid-base combination. Low lying intermediates, which occur in late stages of the catalytic cycle, are another challenge as they increase the overall activation barrier significantly. As a result it is suggested that this novel approach of hydrogen transfer onto N 2 should be extended to other complexes.

Description: A new phosphoramide with formula (4-CH 3 C 6 H 4 S(O) 2 NH)P(O)(NHCH 2 C 6 H 5 ) 2 ( 1 ) was synthesized and characterized by 1 H, 13 C, 31 P NMR, FT-IR spectroscopy, and elemental analysis. The 13 C NMR spectrum displays two sets of signals for the phenyl carbon atoms of the two benzylamine groups (eight peaks) as well as two separated signals for the 4-CH 3 aliphatic carbon atom possibly due to the presence of a prochiral central phosphorus atom. The structure of compound 1 was determined by X-ray crystallography at 121 K. In this structure, the strong intermolecular N–H ··· O=P and N–H ··· O=S plus weak intermolecular C–H ··· O and N–H ··· C(π of benzyl ring) hydrogen bonds create a three-dimensional crystalline network. The DFT calculations both in the gas phase and in four solvents illustrate that this molecule is more stable at B3PW91 than B3LYP level. Interestingly, comparable computational results are obtained in acetone and methanol solvents as well as in DMSO and ethanol. The QTAIM analyses support the covalent/shared character of the C–N, S–C, and N–H bonds, the intermediate character of P=O, P–N, and S=O bonds, and the electrostatic nature of S=O ··· H–N, P=O ··· H–C, and C–H ··· C(π) interactions. The computational data are in very good agreement with the experimental ones.

Description: The syntheses and physicochemical properties of the three dinitrogen complexes [Mo(N 2 ) 2 (tdppme)(PMe 3 )], [Mo(N 2 )(tdppme)(PMe 3 ) 2 ] and [Mo(N 2 ) 2 (tdppme)(PMe 2 Ph)] supported by the tripodal ligand 1,1,1-tris(diphenylphosphinomethyl)ethane (tdppme) are reported. The complexes are characterized by 31 P NMR-, IR- and Raman spectroscopy. The influence of the ligand tdppme on the coordination of PMe 3 , PMe 2 Ph, PMePh 2 , PPh 3 and dcpm (bis(dicyclohexylphosphine) is investigated and compared to earlier results involving dppm and dmpm as co-ligands.

Description: The preparation of ( R 3 Si) 4 Si ( R = ethyl, n -propyl, iso -propyl, n -butyl, and iso -butyl) was attempted using the procedure reported for [(CH 3 ) 3 Si)] 4 Si. 1 The type of alkyl group affected the resulting materials significantly. For R = ethyl, [(C 2 H 5 ) 3 Si] 2 [hexaethyldisilane ( 1 )] was obtained phase pure if careful fractional distillation (under vacuum) was used, otherwise a mixture of 1 , [(C 2 H 5 ) 2 Si] 4 (octaethyltetra-cyclo-silane), and other unidentified product(s) was obtained. For R = n -propyl a mixture of [(CH 3 CH 2 CH) 3 Si] 2 (hexa- n -propyldisilane), [(CH 3 CH 2 CH 2 ) 2 Si] 4 , (octa- n -propyltetra-cyclo-silane), [(CH 3 CH 2 CH 2 ) 3 Si] 4 Si {tetrakis(tri- n -propylsilyl)silane} ( 2 )], and other unidentified product(s) was obtained. From this mixture only 2 , a new and previously unreported compound, was purified. 2 is the second compound of this type to be reported and is characterized by mass spectrometry (MS), elemental analysis (EA), and thermogravimetry (TG). The crystal structure of 2 is also reported [space group R (no.148), a = 17.9249(10) Å, c = 12.2752(7) Å, at 100 K]. For R = iso -propyl pure [{(CH 3 ) 2 CH 2 } 3 Si] 2 [hexa- iso -propyldisilane ( 3 )] was obtained in a good yield. For R = n -butyl or iso -butyl no phase pure compounds were synthesized. The pure compounds prepared have potential as precursors for the currently problematic atomic layer deposition of silicon, as demonstrated by their complete sublimation under thermal analysis. The sublimation temperature is dependent on the size of the molecule.

Description: Reactions of transition metal thiocyanates with 4-(4-chlorobenzyl)pyridine (Clbp) lead to the formation of compounds of composition M (NCS) 2 (4-(4-chlorobenzyl)pyridine) 4 ( Mn-1 , Fe-1/I , Fe-1/II , Ni-1 , and Cd-1 ) and M (NCS) 2 (4-(4-chlorobenzyl)pyridine) 2 ( Mn-2 , Ni-2 , and Cd-2 ). In the crystal structures of compounds M -1 the metal cations are octahedrally coordinated by two terminal N-bonded thiocyanato anions and four Clbp ligands, whereas in compounds M -2 the metal cations are linked by μ-1, 3-bridging anionic ligands. IR spectroscopic investigations show that the value of the asymmetric C–N stretching vibration depends on the coordination mode of the thiocyanato ligand and the nature of the metal cations. The thermal properties were investigated by simultaneous differential thermoanalysis and thermogravimetry as well as temperature dependent X-ray powder diffraction. On heating compound Ni-1 looses half of the Clbp ligands and transforms into Ni-2 . Clbp deficient intermediates were also detected on thermal decomposition of Mn-1 and Fe-1/I but the samples are of low crystallinity and therefore, their structures cannot be determined. Magnetic investigations reveal that Ni-2 shows only Curie-Weiss paramagnetism without any magnetic anomaly.

Description: While hexaborides are known to exhibit n -type semi-conducting or metallic properties, the carbaboride NaB 5 C that crystallizes with the hexaboride-structure type was found to be p -type. It thus complements n -type CaB 6 , which has almost identical structural features [s.g. Pm m , a = 409.25 pm and z / c (B) = 0.2034 for NaB 5 C and a = 415.37 and z / c (B) = 0.201 for CaB 6 ]. Mono-phasic samples were synthesized via solid state reactions of the elements and compacted by spark plasma sintering at high pressures. The thermoelectric properties (thermal diffusivities, electrical conductivities, Seebeck coefficients) were measured up to temperatures as high as 873 K ( S = 80 μV · K –1 ) and compared to that of LaB 2 C 2 and CeB 2 C 2 . These have layered structures and are metallic.

Description: The title compounds and several other new ternary phosphides – all with closely related crystal structures – were prepared mostly by using elemental tin as a flux. ScFe 5 P 3 , Sc(Ta 0.18 Fe 0.82 )Fe 4 P 3 , and ZrFe 5 P 3 are isotypic with YCo 5 P 3 . The crystal structure of the tantalum containing compound was determined from single-crystal X-ray counter data: space group Pnma , a = 1212.5(2) pm, b = 363.0(2) pm, c = 1052.2(2) pm with a residual R = 0.036 for 505 unique structure factors and 30 variable parameters. The Ta atoms occupy only that Fe site with the highest coordination number. The crystal structure of ScRu 6 P 4 (α-UCr 6 P 4 type) was refined from single-crystal data: P m 2, a = 690.0(2) pm, c = 362.5(3) pm; R = 0.023 for 226 F o and 15 variables. The same structure was also found from Guinier powder data for ErRu 6 P 4 and ZrCr 6 P 4 . However, single-crystal film data for the latter compound suggest a superstructure with a doubling of the hexagonal axis. The new compound Nd 2 Ru 12 P 7 is shown from Guinier powder data to crystallize with a hexagonal Zr 2 Fe 12 P 7 type structure. X-ray powder data also confirm Zr 2 Ru 12 P 7 and SmCo 3 P 2 to crystallize with Zr 2 Fe 12 P 7 and HoCo 3 P 2 type structures, respectively. The crystal structure of the phosphide U 2 Cr 30 P 19 is confirmed to be isotypic with Zr 2 Cr 30 P 19 . The same structure was found for the new compound U 2 Mo 30 P 19 . The crystal structures of these and other compounds with a metal to phosphorus ratio close to 2:1 are briefly discussed including that of LiCo 6 P 4 .

Description: ZrO 2 , CaCO 3 , and Fe 4 [Fe(CN) 6 ] 3 hollow nanospheres are prepared via gelatin-stabilized microemulsions. ZrO 2 and CaCO 3 hollow spheres exhibit outer diameters of 10–20 nm, a thickness of the sphere wall of 4 nm and an inner cavity diameter of 6–12 nm; Fe 4 [Fe(CN) 6 ] 3 is with outer diameters of 50–60 nm, a wall thickness of 15 nm, and an inner cavity diameter of 25–30 nm. The hollow nanospheres turn out as readily crystalline although prepared at room-temperature. Gelatin increases the viscosity of the polar micelle phase and thereby reduces the diffusion in the water phase. This measure is essential to obtain hollow spheres and to avoid the formation of massive nanoparticles. All as-prepared hollow nanospheres are characterized by different electron microscopic techniques (STEM, HRTEM), infrared spectroscopy (FT-IR), thermogravimetry (TG), and X-ray diffraction (XRD). In the case of ZrO 2 , the hollow sphere structure is even maintained after thermal removal of gelatin at 600 °C. Moreover, CO 2 sorption analysis shows reversible CO 2 uptake of 96 mg · g –1 (80 bar, 50°°C) at a specific surface area of 98 m 2 · g –1 . As the adsorption of N 2 is much lower (17 mg · g –1 at 80 bar, 50°°C), the ZrO 2 hollow nanospheres can be interesting for CO 2 -N 2 separation as well as catalytical reactions with CO 2 . All hollow nanospheres, and especially CaCO 3 , can become relevant for drug delivery and release.

Description: The 2D-coordination polymer 2 ∞ [Ce 2 Cl 6 (bipy) 4 ] · py (bipy = 4, 4′-bipyridine) shows a 5d-4f centered emission in the soft UV-B region. It was synthesized via the reaction of anhydrous CeCl 3 and 4, 4′-bipyridine in pyridine under solvothermal conditions. The two-dimensional sheet structure consisting of 4, 4′-bipyridine coordinated Ce 2 Cl 6 dimers closes the gap between the known lanthanum 3 ∞ [La 2 Cl 6 (bipy) 5 ] · 4bipy framework and the 2D networks of the formula 2 ∞ [ Ln 2 Cl 6 (bipy) 3 ] · 2bipy from praseodymium on. They differ in the number of coordinating bipy linkers, which decreases along La 〉 Ce 〉 Pr, with the remarkable observation that lanthanum, cerium, and praseodymium exhibit different network constitutions. The structure of 2 ∞ [Ce 2 Cl 6 (bipy) 4 ] · py exhibits a cem topology constituted of double strands, which are diagonally linked by 4, 4′-bipyridine forming trapezoid cavities in-between the strands. The cavities contain intercalated pyridine molecules.

Description: In situ neutron powder diffraction is a very convenient tool for the investigation of chemical reactions, whenever crystalline solids are involved. It may give insight into reaction pathways, thus allowing for strategic synthesis planning, revealing particular intermediate steps and quantifying the reaction kinetics. Although the method is rather straightforward, one is bound to a small number of available neutron sources and the few sufficiently high intensity powder diffractometers there, most of which are briefly described herein. The high penetration depth of thermal neutrons allows for a large range of complex sample environments; however neutron absorption and parasitic scattering have to be carefully considered in the construction of dedicated in situ equipment. Some specific types of sample environment, specially designed for in situ neutron powder diffraction will be discussed such as electrochemical cells, autoclaves for the study of solvothermal reactions, and gas-solid reaction cells. Several examples from inorganic chemistry are being presented, ranging from metal hydrides, nitrides, oxides, and halides, to intermetallic compounds or metal organic frameworks, many of them of importance in applications, e.g. in lithium ion batteries, as magnetic or hard materials, high strength alloys, hydrogen storage, ferroelectric or superconducting materials, or as solid catalysts. In situ neutron powder diffraction often paves the way to a better reaction control in chemical synthesis, to the discovery of metastable compounds or gives insight into technologically relevant processes. These successful applications in inorganic chemistry demonstrate the usefulness of the method of in situ neutron powder diffraction and may encourage the reader to consider neutron diffraction in the repertoire of analytic tools.

Description: The intermetallic compound CaCoSi was synthesized by solid state synthesis and investigated by means of X-ray diffraction (both powder and single crystal method): PbClF type structure, P 4/ nmm (No.129): a = 3.977(1) Å, c = 7.089(5) Å, R 1 = 0.0303, 121 F 2 , 9 variable parameters. CaCoSi contains isolated [CoSi] 2– 2D layers in the ab plane, which are separated by Ca 2+ cations along the c direction. The crystal chemistry and chemical bonding of CaCoSi are discussed in terms of LMTO band structure calculation and analyzed using the Electron Localization Function (ELF).

Description: New monoclinic polymorphs of RE 2 FeSe 2 O 2 ( RE = La, Ce) were synthesized at 800 °C in a NaI/KI flux, and characterized by single-crystal X-ray diffraction ( C 2/ m , Z = 2). mC -La 2 FeSe 2 O 2 and mC -Ce 2 FeSe 2 O 2 represent new structures in the RE 2 FeSe 2 O 2 family, and contain iron atoms exclusively in a distorted octahedral coordination of four selenium and two oxygen atoms. Such FeSe 4 O 2 octahedra occur together with FeSe 4 -tetrahedra if the synthesis temperature increases to 1000 °C, while at 1100 °C all iron atoms are tetrahedrally coordinated by selenium. Even though the polymorph formation is controlled by the synthesis temperature, no phase transformations could be observed. La 2 FeSe 2 O 2 is a semiconductor with a band gap of approximately 0.3 eV and shows antiferromagnetic ordering at T N ≈ 20 K with an effective magnetic moment of 4.35(2) μ B .

Description: Four new compounds with the [Sn 2 S 6 ] 4– anion acting as tetradentate ligand to metal cations of [ TM (phen) 2 ] 2+ complexes ( TM = Fe, Co; phen = 1,10-phenanthroline) were synthesized under solvothermal conditions. The compounds are rare cases where Fe 2+ /Co 2+ cations form bonds to sulfide anions of a thiometallate anion. In the structures of the compounds the {[ TM (phen) 2 ] 2 Sn 2 S 6 } molecule is the main structural motif. The phen ligands of neighboring molecules are oriented in a way that off-center parallel stacking results leading to weak intermolecular interactions. In two of the four compounds a free phen molecule is trapped between adjacent {[ TM (phen) 2 ] 2 Sn 2 S 6 } moieties and an additional H 2 O molecule is located near the two nitrogen atoms of the free phen molecule. The Hirshfeld surface analysis yields a variety of weak intermolecular interactions which may be regarded as essential for the packing arrangement of the different constituents and the stability of the compounds.

Description: A Na 0.35 MnO 2 /CNT nanocomposite is prepared by a simple and low energy consumption hydrothermal method. Its electrochemical performance as an electrode material for asymmetric supercapacitors with aqueous Na 2 SO 4 solution is investigated. In this nanocomposite less than 2 wt-% of CNTs are intermingled with the Na 0.35 MnO 2 nanowires. Quite obviously the introduced CNTs efficiently improve the rate performance of the composite. When the current density increases from 0.1 to 10 A · g –1 , the capacitance decreases only slightly from 163 to 125 F · g –1 . When assembled into an asymmetric aqueous supercapacitor using activated carbon as the counter electrode and an aqueous electrolyte solution of 0.5 mol · L –1 Na 2 SO 4 , Na 0.35 MnO 2 /CNT shows an energy density of 33.5 Wh · kg –1 at a power density of 3 kW · kg –1 based on the weights of the two electrode materials, higher than those for simple Na 0.35 MnO 2 , with an energy density of 28.7 Wh · kg –1 at a power density of 3 kW · kg –1 only. The Na 0.35 MnO 2 /CNT nanocomposite presents excellent cycling behavior, no capacitance fading after 10000 cycles, even when dissolved oxygen is not removed from the electrolyte solution. The results are very promising for practical applications of this electrode material since sodium is much cheaper than lithium and its natural resources are rich.