Synthesis and structure of KInP2O7 obtained from K—In—P—Mo—O melts

1Kyselov, DV, 1Terebilenko, KV, Petrenko, OV, Baumer, VN, 1Slobodyanik, MS
1Taras Shevchenko National University of Kyiv
Dopov. Nac. akad. nauk Ukr. 2018, 6:91-97
Section: Chemistry
Language: Russian
The peculiarities of the crystallization from mixed phosphate — molybdate melts and the structure of $KInP_{2}O_{7}$ have been investigated. The compound crystallizes in a monoclinic system, space group $P21/c (14), a = 7.4092(1), b = 10.3990(1), c = 8.3966(1), β = 106.23(0)°, V = 621.16(36) Å^{3}$. The three-dimensional framework $[InP2O7]_{\infty}$ consists of isolated $InO_{6}$ octahedra interlinked by six pyrophosphate groups. This type of architecture of the anionic sublattice forms hexagonal channels, where potassium cations are located. Doping the host studied with rare-earth metals would open a possibility of its practical application as a base of the phosphors.
Keywords: crystallization, indium, pyrophosphate, single crystal, X-ray diffraction
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