Materials Data on KEuGeS4 by Materials Project

Abstract

KEuGeS4 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of K–S bond distances ranging from 3.35–3.64 Å. Eu3+ is bonded to seven S2- atoms to form distorted EuS7 pentagonal bipyramids that share corners with two equivalent EuS7 pentagonal bipyramids, a cornercorner with one GeS4 tetrahedra, edges with two equivalent EuS7 pentagonal bipyramids, and edges with three equivalent GeS4 tetrahedra. There are a spread of Eu–S bond distances ranging from 2.90–3.03 Å. Ge4+ is bonded to four S2- atoms to form GeS4 tetrahedra that share a cornercorner with one EuS7 pentagonal bipyramid and edges with three equivalent EuS7 pentagonal bipyramids. There are a spread of Ge–S bond distances ranging from 2.20–2.24 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted see-saw-like geometry to one K1+, two equivalent Eu3+, and one Ge4+ atom. In the second S2- site, S2- is bonded to three equivalent K1+, one Eu3+, and one Ge4+ atom to form a mixture of distorted edge and corner-sharing SK3EuGe trigonal bipyramids. In the third S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent K1+, two equivalent Eu3+, and one Ge4+ atom. In the fourth S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent K1+, two equivalent Eu3+, and one Ge4+ atom.