Materials Data on RbGd2CuSe4 by Materials Project
RbGd2CuSe4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Rb1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Rb–Se bond distances ranging from 3.35–3.96 Å. Gd3+ is bonded to six Se2- atoms to form GdSe6 octahedra that share corners with three equivalent GdSe6 octahedra, a cornercorner with one CuSe4 tetrahedra, edges with five equivalent GdSe6 octahedra, and edges with two equivalent CuSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 0–37°. There are a spread of Gd–Se bond distances ranging from 2.86–2.99 Å. Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with two equivalent GdSe6 octahedra, corners with two equivalent CuSe4 tetrahedra, and edges with four equivalent GdSe6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are two shorter (2.47 Å) and two longer (2.48 Å) Cu–Se bond lengths. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to two equivalent Rb1+, two equivalent Gd3+, and two equivalent Cu1+ atoms. In the second Se2- site, Se2- is bonded to two equivalent Rb1+, three equivalent Gd3+, and one Cu1+ atom to form a mixture of distorted edge, face, and corner-sharing SeRb2Gd3Cu octahedra. The corner-sharing octahedra tilt angles range from 4–65°. In the third Se2- site, Se2- is bonded to two equivalent Rb1+ and four equivalent Gd3+ atoms to form a mixture of distorted edge and corner-sharing SeRb2Gd4 octahedra. The corner-sharing octahedra tilt angles range from 4–47°.