Mercury(I) Molybdates and Tungstates: Hg2WO4 and Two Modifications of Hg2MoO4
详细信息 查看全文
- 作者：Thomas J. Mormann and Wolfgang Jeitschko
- 刊名：Inorganic Chemistry
- 出版年：2000
- 出版时间：September 18, 2000
- 年：2000
- 卷：39
- 期：19
- 页码：4219 - 4223
- 全文大小：77K
- 年卷期：v.39,no.19(September 18, 2000)
- ISSN：1520-510X
文摘
The high-temperature (
-) modification of Hg2MoO4 was prepared by solid-state reaction of HgO with MoO2 at400 
C. Well-crystallized samples of the low-temperature (
-) modification of Hg2MoO4 and isotypic Hg2WO4were obtained by hydrothermal recrystallization of the microcrystalline powders at 180 C. The crystal structuresof these transparent yellow compounds were determined by single-crystal X-ray diffractometry. -Hg2MoO4:P21/c, Z = 4, a = 511.31(6) pm, b = 901.83(7) pm, c = 1086.0(1) pm, = 101.01(3). -Hg2MoO4 andHg2WO4: C2/c, Z = 4, a = 873.52(6) and 873.0(1) pm, b = 1155.19(7) and 1147.6(3) pm, c = 493.05(3) and493.24(6) pm, = 115.196(5) and 114.86(1), respectively. In -Hg2MoO4 the molybdenum atoms aretetrahedrally coordinated by oxygen atoms and the MoO4 tetrahedra are linked via Hg2 dumb-bells, thus forminginfinite zigzag chains. The low-temperature (-)modification of Hg2MoO4 contains MoO6 octahedra, which arelinked via common edges to form zigzag chains, which are further linked via Hg2 dumb-bells, resulting in puckeredtwo-dimensionally infinite sheets. Bonding between adjacent sheets is achieved only via weak (secondary) Hg-Obonds of 254.8 pm, while the strong Hg-O bonds of the nearly linear O-Hg-Hg-O groups within the sheetshave a length of 214.8 pm. The Hg-Hg bond lengths are practically the same in the three compounds with252.3(1), 253.49(7), and 253.3(1) pm in -Hg2MoO4, -Hg2MoO4, and Hg2WO4, respectively. The average Mo-Odistances within the MoO4 tetrahedra and the MoO6 octahedra are 176.2, and 196.5 pm, respectively. The structuralchemistry of these compounds is discussed together with that of previously reported mercury I and II molybdatesand tungstates.
-) modification of Hg2MoO4 was prepared by solid-state reaction of HgO with MoO2 at400 C. Well-crystallized samples of the low-temperature (-) modification of Hg2MoO4 and isotypic Hg2WO4were obtained by hydrothermal recrystallization of the microcrystalline powders at 180 C. The crystal structuresof these transparent yellow compounds were determined by single-crystal X-ray diffractometry. -Hg2MoO4:P21/c, Z = 4, a = 511.31(6) pm, b = 901.83(7) pm, c = 1086.0(1) pm, = 101.01(3). -Hg2MoO4 andHg2WO4: C2/c, Z = 4, a = 873.52(6) and 873.0(1) pm, b = 1155.19(7) and 1147.6(3) pm, c = 493.05(3) and493.24(6) pm, = 115.196(5) and 114.86(1), respectively. In -Hg2MoO4 the molybdenum atoms aretetrahedrally coordinated by oxygen atoms and the MoO4 tetrahedra are linked via Hg2 dumb-bells, thus forminginfinite zigzag chains. The low-temperature (-)modification of Hg2MoO4 contains MoO6 octahedra, which arelinked via common edges to form zigzag chains, which are further linked via Hg2 dumb-bells, resulting in puckeredtwo-dimensionally infinite sheets. Bonding between adjacent sheets is achieved only via weak (secondary) Hg-Obonds of 254.8 pm, while the strong Hg-O bonds of the nearly linear O-Hg-Hg-O groups within the sheetshave a length of 214.8 pm. The Hg-Hg bond lengths are practically the same in the three compounds with252.3(1), 253.49(7), and 253.3(1) pm in -Hg2MoO4, -Hg2MoO4, and Hg2WO4, respectively. The average Mo-Odistances within the MoO4 tetrahedra and the MoO6 octahedra are 176.2, and 196.5 pm, respectively. The structuralchemistry of these compounds is discussed together with that of previously reported mercury I and II molybdatesand tungstates.