Materials Data on CaAgAsO4 by Materials Project

Abstract

CaAgAsO4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six equivalent AsO4 tetrahedra and edges with two equivalent CaO6 octahedra. There are two shorter (2.34 Å) and four longer (2.42 Å) Ca–O bond lengths. Ag1+ is bonded in a 6-coordinate geometry to four O2- atoms. There are two shorter (2.30 Å) and two longer (2.59 Å) Ag–O bond lengths. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with six equivalent CaO6 octahedra. The corner-sharing octahedra tilt angles range from 43–52°. There is two shorter (1.71 Å) and two longer (1.74 Å) As–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ag1+, and one As5+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Ca2+, one Ag1+, and one As5+ atom.