A New Lithium Hydrogen Tellurate--LiH5TeO6

X-ray structural analysis for lithium pentahydrogen tellurate has been carried out. The substance crystallizes in a tetragonal system in the space group P42/n, a=7.6350(6), c= 7.5014(9) ?, V=437.28(7) ?3, Z=4, and R=0.0189 for 350 observed reflections. The crystal structure consists of isolated TeO6 octahedra, which are connected by a network of hydrogen bonds. The lithium atoms are surrounded by slightly deformed oxygen octahedra. Infrared and Raman spectra have been studied. The FTIR spectra were recorded down to a temperature of 90 K. Thermal behavior of LiH5TeO6 has been studied by the methods of TG, DTA, DTG, and DSC. Conclusions following from the DSC and FTIR measurements exclude the existence of structural phase transitions in the temperature interval from 90 K to the temperature of decomposition of the compound (390 K).