Structural single crystal, thermal analysis and vibrational studies of the new rubidium phosphate tellurate Rb2HPO4RbH2PO4·Te(OH)6

Abstract

The determination of the crystalline structure of rubidium phosphate tellurate Rb2HPO4RbH2PO4·Te(OH)6 [RbPTe] is performed from single crystal X-ray diffraction data. The title compound crystallizes in the monoclinic system P2. The unit cell parameters are as follows: a = 7.9500(7) Å, b = 6.3085(6) Å, c = 9.5008(9) Å, β = 109.783(4)°, Z = 2 and V = 448.37(7) Å3. The crystal structure is constituted from isolated (PO43-) tetrahedra and (TeO66-) octahedra and two nonequivalent Rb+ cations. Material cohesion is built of O–H⋯O bondings and ionic interactions. The new synthesized material has been characterized using the differential scanning calorimetry (DSC), thermal analysis [differential thermogravimetric analysis (TG), thermodifference analysis (DTA) and the mass spectrometric analysis], FT-IR and Raman techniques. Thermal analysis, in the temperature range of 300–900 K, confirms that the decomposition of this material took place in two steps. The differential scanning calorimetry analysis shows three endothermic peaks at 451, 463 and 481 K. The existence of anionic groups in the structure has been confirmed by IR and Raman spectroscopy in the frequency ranges 3000–600 cm−1 and 1300–50 cm−1, respectively.

Keywords

• Inorganic compound
• X-ray diffraction
• Phase transition
• Thermal behavior
• Spectroscopy study