Interaction trifluorure d'antimoine-seleniates alcalins: Structure cristalline de K 2SeO 4(SbF 3) 2 · H 2O
The systems SbF 3 M2SeO 4 ( M = K, Rb, and Cs) in selenic aqueous solution have been studied. Two kinds of compounds have been isolated: molecular addition compounds K 2SeO 4(SbF 3) 2, Rb 2SeO 4(SbF 3) 2, K 2SeO 4(SbF 3) 2 · H 2O, and double decomposition compounds MSbF 2SeO 4. The crystal structure of K 2SeO 4(SbF 3) 2 · H 2O has been solved from an X-ray single crystal study (orthorhombic P2 12 12 1, R = 0.033 with 1251 reflexions). There are two types of antimony atoms both with monocapped octahedral environment 3.3.1 AX 6E. The SeO 4 entities weakly linked with four antimony atoms show a tetrahedral geometry slightly distorded. Infrared and Raman spectra of the different phases which have been synthesized show a more important distortion of the SeO 4 group in the MSbF 2SeO 4 compounds wherein the SbF 2 groups are more strongly linked.