Materials Data on Ca2CdP2 by Materials Project

Abstract

Ca2CdP2 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to five P3- atoms to form CaP5 square pyramids that share corners with four equivalent CaP5 square pyramids, corners with four equivalent CdP4 tetrahedra, corners with seven equivalent CaP5 trigonal bipyramids, edges with two equivalent CaP5 square pyramids, edges with three equivalent CdP4 tetrahedra, and edges with two equivalent CaP5 trigonal bipyramids. There are a spread of Ca–P bond distances ranging from 2.89–3.09 Å. In the second Ca2+ site, Ca2+ is bonded to five P3- atoms to form distorted CaP5 trigonal bipyramids that share corners with seven equivalent CaP5 square pyramids, corners with two equivalent CdP4 tetrahedra, corners with four equivalent CaP5 trigonal bipyramids, edges with two equivalent CaP5 square pyramids, edges with four equivalent CdP4 tetrahedra, and edges with four equivalent CaP5 trigonal bipyramids. There are a spread of Ca–P bond distances ranging from 2.88–3.02 Å. Cd2+ is bonded to four P3- atoms to form CdP4 tetrahedra that share corners with four equivalent CaP5 square pyramids, corners with four equivalent CdP4 tetrahedra, corners with two equivalent CaP5 trigonal bipyramids, edges with three equivalent CaP5 square pyramids, and edges with four equivalent CaP5 trigonal bipyramids. There are a spread of Cd–P bond distances ranging from 2.59–2.77 Å. There are two inequivalent P3- sites. In the first P3- site, P3- is bonded in a 8-coordinate geometry to six Ca2+ and two equivalent Cd2+ atoms. In the second P3- site, P3- is bonded to four Ca2+ and two equivalent Cd2+ atoms to form a mixture of distorted edge and corner-sharing PCa4Cd2 octahedra. The corner-sharing octahedral tilt angles are 75°.