Materials Data on K2UCu3S5 by Materials Project

Abstract

K2UCu3S5 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. K1+ is bonded to seven S2- atoms to form distorted KS7 pentagonal bipyramids that share corners with two equivalent US6 octahedra, corners with two equivalent KS7 pentagonal bipyramids, corners with nine CuS4 tetrahedra, edges with three equivalent US6 octahedra, edges with three equivalent KS7 pentagonal bipyramids, edges with four CuS4 tetrahedra, and faces with two equivalent KS7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 22°. There are a spread of K–S bond distances ranging from 3.25–3.32 Å. U4+ is bonded to six S2- atoms to form US6 octahedra that share corners with four equivalent KS7 pentagonal bipyramids, corners with two equivalent CuS4 tetrahedra, edges with two equivalent US6 octahedra, edges with six equivalent KS7 pentagonal bipyramids, and edges with four equivalent CuS4 tetrahedra. There are two shorter (2.60 Å) and four longer (2.68 Å) U–S bond lengths. There are two inequivalent Cu+1.33+ sites. In the first Cu+1.33+ site, Cu+1.33+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with two equivalent US6 octahedra, corners with eight equivalent KS7 pentagonal bipyramids, corners with two equivalent CuS4 tetrahedra, edges with two equivalent KS7 pentagonal bipyramids, and edges with four equivalent CuS4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. There are two shorter (2.36 Å) and two longer (2.41 Å) Cu–S bond lengths. In the second Cu+1.33+ site, Cu+1.33+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with five equivalent KS7 pentagonal bipyramids, corners with three equivalent CuS4 tetrahedra, edges with two equivalent US6 octahedra, edges with three equivalent KS7 pentagonal bipyramids, and edges with two equivalent CuS4 tetrahedra. There are a spread of Cu–S bond distances ranging from 2.30–2.38 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to two equivalent K1+, one U4+, and three Cu+1.33+ atoms. In the second S2- site, S2- is bonded in a 6-coordinate geometry to three equivalent K1+, two equivalent U4+, and one Cu+1.33+ atom. In the third S2- site, S2- is bonded in a 8-coordinate geometry to four equivalent K1+ and four Cu+1.33+ atoms.