Materials Data on K2TbO3 by Materials Project

Abstract

K2TbO3 is High Pressure (4-7GPa) Tellurium-derived structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.62–3.02 Å. In the second K1+ site, K1+ is bonded to six O2- atoms to form distorted KO6 octahedra that share corners with two equivalent KO6 octahedra, edges with two equivalent KO6 octahedra, and edges with six TbO6 octahedra. The corner-sharing octahedral tilt angles are 20°. All K–O bond lengths are 2.75 Å. In the third K1+ site, K1+ is bonded to six O2- atoms to form distorted KO6 octahedra that share corners with two equivalent KO6 octahedra, corners with four TbO6 octahedra, edges with two equivalent KO6 octahedra, and edges with four TbO6 octahedra. The corner-sharing octahedra tilt angles range from 16–20°. There are a spread of K–O bond distances ranging from 2.60–2.98 Å. There are two inequivalent Tb4+ sites. In the first Tb4+ site, Tb4+ is bonded to six O2- atoms to form TbO6 octahedra that share corners with two equivalent KO6 octahedra, edges with three equivalent TbO6 octahedra, and edges with five KO6 octahedra. The corner-sharing octahedral tilt angles are 16°. There are two shorter (2.30 Å) and four longer (2.31 Å) Tb–O bond lengths. In the second Tb4+ site, Tb4+ is bonded to six O2- atoms to form TbO6 octahedra that share corners with two equivalent KO6 octahedra, edges with three equivalent TbO6 octahedra, and edges with five KO6 octahedra. The corner-sharing octahedral tilt angles are 16°. All Tb–O bond lengths are 2.31 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to four K1+ and two Tb4+ atoms. In the second O2- site, O2- is bonded in a 6-coordinate geometry to four K1+ and two Tb4+ atoms. In the third O2- site, O2- is bonded in a 6-coordinate geometry to four K1+ and two Tb4+ atoms.