ISSN:
0044-2313
Keywords:
New oxides of divalent copper
;
crystal structure
;
MAPLE
;
absorption spectra
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Synthesis, Crystal Structures, and Absorption Spectra of the New “Cupriosilicates”: K6[CuSi2O8] and Rb4[CuSi2O7]K6[CuSi2O8] and Rb4[CuSi2O7] were obtained by annealing intimate mixtures of K2O and Rb2O, respectively, CuO and SiO2 in sealed Ag cylinders at 500°C as transparent greenish-blue single crystals. The structure solution (IPDS-data Mo Kα; K6[CuSi2O8]: 1292 F2(hkl), R1 = 0.059; wR2 = 0.103 and Rb4[CuSi2O7]: 763 F2(hkl), R1 = 0.049; wR2 = 0.114) confirms the space group P1 for both compounds. K6[CuSi2O8]: a = 619.4(2); b = 665.5(2); c = 753.0(2) pm; α = 83.66(3); β = 87.71(3); γ = 70.19(3)°; Z = 1. Rb4[CuSi2O7]: a = 631.9(9); b = 707.5(10); c = 715.2(6) pm; α = 114.2(1); β = 100.7(1); γ = 107.9(1)°; Z = 1. The Madelung Part of the Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these calculated via Mean Effective Ionic Radii, MEFIR, are given. The absorption spectra of K6[CuSi2O8] and Rb4[CuSi2O7] are discussed in terms of the Angular Overlap Model, AOM.
Notes:
K6[CuSi2O8] und Rb4[CuSi2O7] wurden erstmals durch Tempern innig verriebener Gemenge aus K2O bzw. Rb2O, CuO und SiO2 in verschlossenen Ag-Zylindern bei 500°C in Form von transparenten blaugrünen Einkristallen erhalten. Die Strukturaufklärung (IPDS-Datensätze, Mo-Kα; K6[CuSi2O8]: 1292 F2(hkl), R1 = 0,059; wR2 = 0,103 und Rb4[CuSi2O7]: 763 F2(hkl), R1 = 0,049; wR2 = 0,114) belegt die Raumgruppe P1 für beide Verbindungen. K6[CuSi2O8]: a = 619,4(2); b = 665,5(2); c = 753,0(2) pm; α = 83,66(3); β = 87,71(3); γ = 70,19(3)°; Z = 1. Rb4[CuSi2O7]: a = 631,9(9); b = 707,5(10); c = 715,2(6) pm; α = 114,2(1); β = 100,7(1); γ = 107,9(1)°; Z = 1. Der Madelunganteil der Gitterenergie, MAPLE, sowie Effektive Koordinationszahlen, ECoN, aus Mittleren Fiktiven Ionenradien, MEFIR, erhalten, werden angegeben. Die Absorptionsspektren von K6[CuSi2O8] und Rb4[CuSi2O7] werden anhand des Angular-Overlap-Modells, AOM, diskutiert.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/zaac.19976231102
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