Mohamed Dammak, Ikram Bechibani, Lilia Ktari and Santiago Garcia-Granda
Inorganic Chemistry Laboratory, University of Sfax Tunisia, Sfax, Tunisia
The new rubidium arsenate tellurate material was synthesized by slow evaporation at room temperature from an aqueous solution of telluric acid- arsenic acid and rubidium carbonate. Crystal structure of Rb2HAsO4.Te (OH) 6 (RbAsTe) crystallizes at room temperature 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 thermal analysis ((D.T.A) and (TG)) of the title compound show that the decomposition of this material start at temperature equal to 500 K and the differential scanning calorimetry (DSC) analysis shows three phase transitions at 332 K, 464 K and 476 K. In order to confirm that the first phase transition is structural one we have made the X-Ray single crystal at high temperature (363 K). Indeed, at 363 K the RbAsTe material crystallizes in the monoclinic space group I2/a with the following cell parameters: a= 16.727(11) Å, b= 7.133(6) Å, c= 12.481(10) Å and β= 90.29(6). Raman spectra of the title compound recorded at 299 K and 410 K in the frequency range (50-1000 cm-1) show the presence of order and disorder phenomenon in the RbAsTe compound and confirm that the anionic groups coexist independently in the same crystal.
Keywords: Biological Sructure New material, nano material.