Premium
Synthesis and characterization of phosphates in the pseudo‐ternary melted systems Cs 2 O‐P 2 O 5 ‐M II O (M II – alkaline earth)
Author(s) -
Zatovsky I. V.,
Strutynska N. Yu.,
Slobodyanik N. S.,
Baumer V. N.,
Shishkin O. V.
Publication year - 2008
Publication title -
crystal research and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.377
H-Index - 64
eISSN - 1521-4079
pISSN - 0232-1300
DOI - 10.1002/crat.200711077
Subject(s) - crystallography , monoclinic crystal system , crystallization , octahedron , alkali metal , crystal structure , chemistry , ternary operation , x ray crystallography , caesium , analytical chemistry (journal) , diffraction , inorganic chemistry , physics , organic chemistry , computer science , programming language , chromatography , optics
The crystallization of alkali‐earth phosphates in the melts of Cs 2 O‐P 2 O 5 ‐M II O (M II – Ca, Sr, Ba) pseudo‐ternary systems have been investigated at various Cs/P molar ratios and at fixed value of M II /P equal to 0.15. Type of the phosphate which crystallizes in melts depends on the Cs/P initial ratio. Crystallization fields of CsM II P 3 O 9 , M II 2 P 2 O 7 and Cs 2 M II P 2 O 7 were briefly investigated and characterized. The new diphosphate Cs 2 CaP 2 O 7 has been obtained and investigated by the single crystal and powder X‐ray diffraction and FTIR‐ spectroscopy. It crystallizes in C 2/m space group, with the following parameters of the monoclinic cell: a = 10.261(2), b = 5.9316(12), c = 7.2404(14) Å, β = 118.54(3)°. The architecture of [CaP 2 O 7 ] 2‐ anionic sublattice, which is built up from [CaO 6 ] octahedra and [P 2 O 7 ] bitetrahedra, interlinked via the common oxygen vertices, gives rise to formation of hexagonal tunnels along crystallographic direction b , where caesium atoms are located. One of the most remarkable features of the structure is specific positional disorder of the diphosphate group, which is connected with the existence of two equiprobable half‐occupied sites of the bridging oxygen. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)