Materials Data on Cs2K2TeO5 by Materials Project

Cs2K2TeO5 crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded to six O2- atoms to form distorted CsO6 octahedra that share corners with six equivalent TeO5 trigonal bipyramids and an edgeedge with one CsO6 octahedra. There are a spread of Cs–O bond distances ranging from 2.91–3.21 Å. In the second Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (3.25 Å) and four longer (3.47 Å) Cs–O bond lengths. K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.72–2.90 Å. Te6+ is bonded to five O2- atoms to form TeO5 trigonal bipyramids that share corners with six equivalent CsO6 octahedra. The corner-sharing octahedra tilt angles range from 1–45°. There are a spread of Te–O bond distances ranging from 1.90–1.96 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three Cs1+, two equivalent K1+, and one Te6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three Cs1+, three equivalent K1+, and one Te6+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Cs1+, two equivalent K1+, and one Te6+ atom.