Materials Data on Rb2TaCuS4 by Materials Project
Rb2TaCuS4 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Rb1+ is bonded to eight equivalent S2- atoms to form distorted RbS8 hexagonal bipyramids that share corners with four equivalent RbS8 hexagonal bipyramids, corners with two equivalent TaS4 tetrahedra, corners with four equivalent CuS4 tetrahedra, edges with six equivalent RbS8 hexagonal bipyramids, edges with two equivalent CuS4 tetrahedra, edges with three equivalent TaS4 tetrahedra, and faces with two equivalent RbS8 hexagonal bipyramids. There are a spread of Rb–S bond distances ranging from 3.52–3.74 Å. Ta5+ is bonded to four equivalent S2- atoms to form TaS4 tetrahedra that share corners with four equivalent RbS8 hexagonal bipyramids, edges with six equivalent RbS8 hexagonal bipyramids, and edges with two equivalent CuS4 tetrahedra. All Ta–S bond lengths are 2.30 Å. Cu1+ is bonded to four equivalent S2- atoms to form CuS4 tetrahedra that share corners with eight equivalent RbS8 hexagonal bipyramids, edges with four equivalent RbS8 hexagonal bipyramids, and edges with two equivalent TaS4 tetrahedra. All Cu–S bond lengths are 2.35 Å. S2- is bonded in a 6-coordinate geometry to four equivalent Rb1+, one Ta5+, and one Cu1+ atom.