Structural, dielectric and vibrational studies in the dipotassium sulfate selenate tellurate mixed solid solution

Synthesis, crystal structure, DSC characterization, dielectric and Raman measurements are given for a new mixed solution K2(SO4)0.9(SeO4)0.1·Te(OH)6 (KSSeTe). X-ray studies showed that the title compound crystallizes in the triclinic system (P1¯) with the following parameters: a = 6.2560(3) Å, b = 6.5680(3) Å, c = 13.1550(6) Å, α = 102.30(2)°, β = 90.07(2)°, γ = 116.98(2)°, Z = 2, V = 474.60(4) Å3 and ρcal = 2.86 g cm−3. The structure can be regarded as being built of isolated TeO6 octahedra, SO4 and SeO4 tetrahedra and K+ cations. The main feature of this structure is the coexistence of three different anions (TeO66−, SO42− and SeO42− groups) in the unit cell, connected by OH⋯O hydrogen bonds.Crystals of K2(SO4)0.9(SeO4)0.1·Te(OH)6 undergo three endothermic peaks at 425 K, 465 K and 480 K. These transitions detected by DSC and analyzed by dielectric measurements using the impedance and modulus spectroscopy techniques.IR and Raman scattering measurements on K2(SO4)0.9(SeO4)0.1·Te(OH)6 material taken between 300 K and 620 K are reported in this paper. The spectra indicate clearly these phase transitions.