Publication Date:
2020-03-05
Description:
The judicious selection of suitable ligands is vitally important in the construction of novel metal–organic frameworks (MOFs) with fascinating structures and interesting properties. Recently, imidazole-containing multidentate ligands have received much attention. Two new CdII coordination frameworks, namely, poly[tris{μ-1,4-bis[(1H-imidazol-1-yl)methyl]benzene-κ2 N 3:N 3′}tetrakis(nitrato-κ2 O,O′)dicadmium], [Cd2(NO3)4(C14H14N4)3] n , (I), and poly[[bis{μ3-1,3,5-tris[(1H-imidazol-1-yl)methyl]benzene-κ3 N 3:N 3′:N 3′′}cadmium] hexafluorosilicate], {[Cd(C18H18N6)2](SiF6)} n , (II), have been synthesized and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. In polymer (I), the 1,4-bis[(1H-imidazol-1-yl)methyl]benzene ligand bridges Cd2+ ions with a distorted seven-coordinated pentagonal bipyramidal geometry, forming a one-dimensional ladder chain, and the nitrate anions coordinate to the Cd2+ ions in a terminal bidentate fashion. In the crystal, adjacent chains are further connected by C—H...O hydrogen bonds to generate a two-dimensional (2D) supramolecular structure. Polymer (II) exhibits a 2D layered structure in which 1,3,5-tris[(1H-imidazol-1-yl)methyl] benzene ligands join Cd2+ centres having a six-coordinated octahedral structure. The layers are connected by hexafluorosilicate anions via C—H...F hydrogen-bond interactions, giving rise to a three-dimensional supramolecular network structure in the solid state. In addition, powder X-ray diffraction (PXRD) patterns were recorded, thermogravimetric analyses (TGA) carried out and fluorescence properties investigated.
Electronic ISSN:
2053-2296
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
