Materials Data on YbCu5S4 by Materials Project

YbCu5S4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Yb3+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with twelve CuS4 tetrahedra, edges with two equivalent YbS6 octahedra, edges with four equivalent CuS6 octahedra, and edges with six CuS4 tetrahedra. There are four shorter (2.72 Å) and two longer (2.74 Å) Yb–S bond lengths. There are three inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to six S2- atoms to form CuS6 octahedra that share corners with twelve CuS4 tetrahedra, edges with two equivalent CuS6 octahedra, edges with four equivalent YbS6 octahedra, and edges with six CuS4 tetrahedra. There are four shorter (2.67 Å) and two longer (2.68 Å) Cu–S bond lengths. In the second Cu1+ site, Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share a cornercorner with one YbS6 octahedra, corners with five equivalent CuS6 octahedra, corners with six CuS4 tetrahedra, an edgeedge with one CuS6 octahedra, edges with two equivalent YbS6 octahedra, and edges with three CuS4 tetrahedra. The corner-sharing octahedra tilt angles range from 16–56°. There are a spread of Cu–S bond distances ranging from 2.36–2.42 Å. In the third Cu1+ site, Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share a cornercorner with one CuS6 octahedra, corners with five equivalent YbS6 octahedra, corners with six CuS4 tetrahedra, an edgeedge with one YbS6 octahedra, edges with two equivalent CuS6 octahedra, and edges with three CuS4 tetrahedra. The corner-sharing octahedra tilt angles range from 14–55°. There are a spread of Cu–S bond distances ranging from 2.29–2.41 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to two equivalent Yb3+ and five Cu1+ atoms to form a mixture of distorted edge and corner-sharing SYb2Cu5 pentagonal bipyramids. In the second S2- site, S2- is bonded to one Yb3+ and six Cu1+ atoms to form distorted SYbCu6 pentagonal bipyramids that share corners with three equivalent SYbCu6 pentagonal bipyramids and edges with twelve SYb2Cu5 pentagonal bipyramids.