Crystal structure of a new gallium tellurite: Ga2Te4O11

Ga₂Te₄O₁₁ crystallises with triclinic symmetry (space group P1) and unit cell parameters: a = 5.125(1) Å, b = 6.559(1) Å, c = 8.173(2) Å, α = 75.06(2), β = 89.25(2), γ = 69.62(2), Z = 1. Its crystal structure has been refined by a full matrix least-squares process to R₁ = 0.023 and wR₂ = 0.060 values, on the basis of 2931 independent single crystal X-ray reflections. It can be described as a three-dimensional polyhedral network of independent Te₂O₆ groups of TeO₃ trigonal pyramids and TeO₄ disphenoids sharing corners, and infinite (Te₂O₅)_∞ quasi-linear chains of the same corner-sharing TeO₃ and TeO₄ units, linked one to the other via common corner or common edge by GaO₄ and GaO₅ polyhedra. The stereochemical activity of the lone pair of each Te atom has been analysed and a comparison is made with all the known other M₂Te₄O₁₁ crystal structures.