(KIn0.33Te0.67Te2O7)-Te-III-Te-VI-O-IV: Zirconolite-like Mixed-Valent Metal Oxide with a 3D Framework

Abstract

We provide the material synthesis method, crystal structure information, and characterization of a novel mixed-valent metal oxide (KIn0.33Te0.67Te2O7)-Te-III-Te-VI-O-IV, closely related to zirconolite (CaZrTi2O7), a radioactive waste immobilized material, having a 3D framework. The reported metal oxide containing an alkali-metal cation (K+), main-group cation (In3+), tellurate, and tellurite has been synthesized as both single crystals and a pure polycrystalline phase through a hydrothermal synthesis method. Single-crystal X-ray diffraction indicates that KIn0.33Te2.67O7 crystallizing in the orthorhombic space group Cmcm (No. 63) reveals a 3D framework structure with a 1D channel consisting of Te/InO6 octahedra and TeO4 polyhedra. An interesting transition reaction from KIn0.33Te2.67O7 to KIn(TeO3)(2) under hydrothermal conditions at 230 degrees C is discussed.