Crystal Structure and Thermochemical Properties of a First Scandium Borophosphate, Sc(H2O)2[BP2O8]·H2O
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- 作者：Bastian Ewald ; Yurii Prots ; Christian Kudla ; Daniel Grü ; ner ; Raul Cardoso-Gil ; and Rü ; diger Kniep
- 刊名：Chemistry of Materials
- 出版年：2006
- 出版时间：February 7, 2006
- 年：2006
- 卷：18
- 期：3
- 页码：673 - 679
- 全文大小：400K
- 年卷期：v.18,no.3(February 7, 2006)
- ISSN：1520-5002
文摘
Crystalline samples of scandium borophosphate, Sc(H2O)[BP2O8]·H2O, were synthesized hydrothermallyfrom acidic suspensions of scandium sesquioxide and boric and phosphoric acid at 443 K. The chiralcrystal structure (space group P6522 (No. 179), a = 957.52(3) pm, c = 1581.45(6) pm, Z = 6) wassolved from single-crystal data and contains helical chain anions 
of alternating borate andphosphate tetrahedra interconnected by ScO4(H2O)2 coordination octahedra. On thermal treatment, areversible release of the hydrate water from the structural channels is observed, and rehydation appearsas soon as the compound is exposed to air moisture for at least 1 day. X-ray powder diffractions showthat the structure is retained during the de-/rehydration process. Both the crystal structure of the dehydratedphase, Sc(H2O)2[BP2O8] (a = 953.5(1) pm, c = 1576.8(2) pm), and that of the rehydrated phase, whichis identical to the hydrothermal product, were refined from X-ray powder data with Rietveld methods.When the dehydrated phase is exposed to an ammonia atmosphere, NH3 absorption is observed.
of alternating borate andphosphate tetrahedra interconnected by ScO4(H2O)2 coordination octahedra. On thermal treatment, areversible release of the hydrate water from the structural channels is observed, and rehydation appearsas soon as the compound is exposed to air moisture for at least 1 day. X-ray powder diffractions showthat the structure is retained during the de-/rehydration process. Both the crystal structure of the dehydratedphase, Sc(H2O)2[BP2O8] (a = 953.5(1) pm, c = 1576.8(2) pm), and that of the rehydrated phase, whichis identical to the hydrothermal product, were refined from X-ray powder data with Rietveld methods.When the dehydrated phase is exposed to an ammonia atmosphere, NH3 absorption is observed.