Structural, thermal behavior and vibrational studies of the new rubidium arsenate tellurate Rb2HAsO4·Te(OH)6

Crystal structure of Rb2HAsO4·Te(OH)6 crystallizes in the monoclinic system space group P21/c. The unit cell parameters are a = 8.344(2) Å, b = 7.12(10) Å, c = 12.453(2) Å and β = 90.28(1)°. The main feature of this atomic arrangement is the coexistence of two independent and different anions (AsO43- and TeO66-) in the unit cell, connected by hydrogen bonds (O–H⋯O) which make the building of the crystal. The arrangement of different polyhedral in the structure forming tunnels where cations Rb+ are placed. The Raman and IR spectra recorded at room temperature, in the frequency ranges (50–1300) cm−1 and (4000–400) cm−1, respectively, confirm the presence of AsO43- and TeO66- groups and elucidate the hydrogen bonds in their crystal lattice. The thermal analysis ((DTA) and (TG)) of the title compound show that the decomposition of this material start at a temperature equal to 500 K and the differential scanning calorimetry (DSC) analysis shows three phase transitions at 332 K, 464 K and 476 K.