Materials Data on CsTb2Ag3Se5 by Materials Project

Abstract

CsTb2Ag3Se5 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Cs1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.63–3.81 Å. Tb3+ is bonded to six Se2- atoms to form TbSe6 octahedra that share a cornercorner with one TbSe6 octahedra, corners with four equivalent AgSe4 tetrahedra, edges with four equivalent TbSe6 octahedra, and edges with five AgSe4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. There are a spread of Tb–Se bond distances ranging from 2.89–2.96 Å. There are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to four Se2- atoms to form AgSe4 tetrahedra that share corners with six AgSe4 tetrahedra and edges with four equivalent TbSe6 octahedra. There are two shorter (2.64 Å) and two longer (2.73 Å) Ag–Se bond lengths. In the second Ag1+ site, Ag1+ is bonded to four Se2- atoms to form distorted AgSe4 tetrahedra that share corners with four equivalent TbSe6 octahedra, corners with four AgSe4 tetrahedra, edges with three equivalent TbSe6 octahedra, and an edgeedge with one AgSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 7–59°. There are a spread of Ag–Se bond distances ranging from 2.70–2.79 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 7-coordinate geometry to two equivalent Cs1+, two equivalent Tb3+, and three Ag1+ atoms. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to two equivalent Cs1+, two equivalent Tb3+, and two equivalent Ag1+ atoms. In the third Se2- site, Se2- is bonded in a 6-coordinate geometry to one Cs1+, three equivalent Tb3+, and two equivalent Ag1+ atoms.