Materials Data on CaYAlO4 by Materials Project

Abstract

CaYAlO4 is (La,Ba)CuO4-derived structured and crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. Ca2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ca–O bond distances ranging from 2.25–2.62 Å. Y3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Y–O bond distances ranging from 2.24–2.62 Å. Al3+ is bonded to six O2- atoms to form corner-sharing AlO6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are a spread of Al–O bond distances ranging from 1.85–2.05 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to one Ca2+, four equivalent Y3+, and one Al3+ atom to form distorted OCaY4Al octahedra that share corners with seventeen OCa2Y2Al2 octahedra, edges with eight OCaY4Al octahedra, and faces with four equivalent OCa2Y2Al2 octahedra. The corner-sharing octahedra tilt angles range from 0–53°. In the second O2- site, O2- is bonded to four equivalent Ca2+, one Y3+, and one Al3+ atom to form distorted OCa4YAl octahedra that share corners with seventeen OCa2Y2Al2 octahedra, edges with eight OCaY4Al octahedra, and faces with four equivalent OCa2Y2Al2 octahedra. The corner-sharing octahedra tilt angles range from 0–54°. In the third O2- site, O2- is bonded to two equivalent Ca2+, two equivalent Y3+, and two equivalent Al3+ atoms to form a mixture of distorted edge, face, and corner-sharing OCa2Y2Al2 octahedra. The corner-sharing octahedra tilt angles range from 8–54°.