Materials Data on Cr8Cd3CuS16 by Materials Project

Abstract

Cr8CuCd3S16 is Spinel-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are four inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with two equivalent CuS4 tetrahedra, corners with four CdS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.38–2.44 Å. In the second Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share a cornercorner with one CuS4 tetrahedra, corners with five CdS4 tetrahedra, and edges with six CrS6 octahedra. There are a spread of Cr–S bond distances ranging from 2.39–2.43 Å. In the third Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with three equivalent CuS4 tetrahedra, corners with three equivalent CdS4 tetrahedra, and edges with six CrS6 octahedra. There are three shorter (2.41 Å) and three longer (2.44 Å) Cr–S bond lengths. In the fourth Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with six CdS4 tetrahedra and edges with six CrS6 octahedra. There are three shorter (2.41 Å) and three longer (2.42 Å) Cr–S bond lengths. Cu2+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 54–59°. There are one shorter (2.33 Å) and three longer (2.34 Å) Cu–S bond lengths. There are three inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 60–61°. There are three shorter (2.51 Å) and one longer (2.53 Å) Cd–S bond lengths. In the second Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 60–61°. There are three shorter (2.50 Å) and one longer (2.52 Å) Cd–S bond lengths. In the third Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 tetrahedra that share corners with twelve CrS6 octahedra. The corner-sharing octahedra tilt angles range from 59–62°. There are one shorter (2.47 Å) and three longer (2.48 Å) Cd–S bond lengths. There are eight inequivalent S2- sites. In the first S2- site, S2- is bonded to three Cr3+ and one Cd2+ atom to form a mixture of distorted edge and corner-sharing SCr3Cd tetrahedra. In the second S2- site, S2- is bonded to three Cr3+ and one Cd2+ atom to form distorted SCr3Cd tetrahedra that share corners with seven SCr3Cd tetrahedra, corners with two equivalent SCr3Cu trigonal pyramids, and edges with three SCr3Cd tetrahedra. In the third S2- site, S2- is bonded to three equivalent Cr3+ and one Cd2+ atom to form a mixture of edge and corner-sharing SCr3Cd tetrahedra. In the fourth S2- site, S2- is bonded to three equivalent Cr3+ and one Cd2+ atom to form distorted SCr3Cd tetrahedra that share corners with nine SCr3Cd tetrahedra, corners with three equivalent SCr3Cu trigonal pyramids, and edges with three equivalent SCr3Cd tetrahedra. In the fifth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Cu2+ atom. In the sixth S2- site, S2- is bonded to three Cr3+ and one Cd2+ atom to form distorted SCr3Cd tetrahedra that share corners with twelve SCr3Cd tetrahedra, edges with two equivalent SCr3Cd tetrahedra, and an edgeedge with one SCr3Cu trigonal pyramid. In the seventh S2- site, S2- is bonded to three equivalent Cr3+ and one Cd2+ atom to form distorted corner-sharing SCr3Cd tetrahedra. In the eighth S2- site, S2- is bonded to three equivalent Cr3+ and one Cu2+ atom to form a mixture of distorted edge and corner-sharing SCr3Cu trigonal pyramids.