Syntheses, Structures, Ionic Conductivities, and Magnetic Properties of Three New Transition-Metal Borophosphates Na5(H3O){MII3[B3O3(O
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- 作者：Miao Yang ; Jihong Yu ; Jiancheng Di ; Jiyang Li ; Peng Chen ; Qianrong Fang ; Yan Chen ; and Ruren Xu
- 刊名：Inorganic Chemistry
- 出版年：2006
- 出版时间：May 1, 2006
- 年：2006
- 卷：45
- 期：9
- 页码：3588 - 3593
- 全文大小：216K
- 年卷期：v.45,no.9(May 1, 2006)
- ISSN：1520-510X
文摘
Three new open-framework transition-metal borophosphates Na5(H3O){MII3[B3O3(OH)]3(PO4)6}·2H2O (MII = Mn,Co, Ni) (denoted as MBPO-CJ25) have been synthesized under mild hydrothermal conditions. Single-crystal X-raydiffraction analyses reveal that the three compounds possess isostructural three-dimensional (3D) open frameworkswith one-dimensional 12-ring channels along the [001] direction. Notably, the structure can also be viewed ascomposed of metal phosphate layers [MII(PO4)2]4- with Kagomé topology, which are further connected by [B3O7(OH)] triborates, giving rise to a 3D open framework. The guest water molecules locate in the 12-ring channels.Partial Na+ ions reside in the 10-ring side pockets within the wall of the 12-ring channels, and the other Na+ ionsand protonated water molecules locate in the 6-ring windows delimited by MO6 and PO4 polyhedra to compensatefor the negative charges of the anionic framework. These compounds show a high thermal stability and are stableupon calcinations at ca. 500 
C. Ionic conductivities, due to the motion of Na+ ions, are measured for these threecompounds. They have similar activation energies of 1.13-1.25 eV and conductivities of 2.7 × 10-7-9.9 × 10-7S cm-1 at 300 C. Magnetic measurements reveal that there are very weak antiferromagnetic interactions amongthe metal centers of the three compounds. Crystal data: MnBPO-CJ25, hexagonal, P63/m (No. 176), a = 11.9683(5)Å, c = 12.1303(6) Å, and Z = 2; CoBPO-CJ25, hexagonal, P63/m (No. 176), a = 11.7691(15) Å, c = 12.112(2)Å, and Z = 2; NiBPO-CJ25, hexagonal, P63/m (No. 176), a = 11.7171(5) Å, c = 12.0759(7) Å, and Z = 2.
C. Ionic conductivities, due to the motion of Na+ ions, are measured for these threecompounds. They have similar activation energies of 1.13-1.25 eV and conductivities of 2.7 × 10-7-9.9 × 10-7S cm-1 at 300 C. Magnetic measurements reveal that there are very weak antiferromagnetic interactions amongthe metal centers of the three compounds. Crystal data: MnBPO-CJ25, hexagonal, P63/m (No. 176), a = 11.9683(5)Å, c = 12.1303(6) Å, and Z = 2; CoBPO-CJ25, hexagonal, P63/m (No. 176), a = 11.7691(15) Å, c = 12.112(2)Å, and Z = 2; NiBPO-CJ25, hexagonal, P63/m (No. 176), a = 11.7171(5) Å, c = 12.0759(7) Å, and Z = 2.