Materials Data on SrCaCr2O6 by Materials Project

Abstract

SrCaCr2O6 is (Cubic) Perovskite-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, corners with eight equivalent CaO12 cuboctahedra, faces with two equivalent CaO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, and faces with eight equivalent CrO6 octahedra. There are four shorter (2.70 Å) and eight longer (2.77 Å) Sr–O bond lengths. Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with four equivalent CaO12 cuboctahedra, corners with eight equivalent SrO12 cuboctahedra, faces with two equivalent SrO12 cuboctahedra, faces with four equivalent CaO12 cuboctahedra, and faces with eight equivalent CrO6 octahedra. There are four shorter (2.70 Å) and eight longer (2.71 Å) Ca–O bond lengths. Cr4+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six equivalent CrO6 octahedra, faces with four equivalent SrO12 cuboctahedra, and faces with four equivalent CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Cr–O bond distances ranging from 1.91–1.99 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Sr2+ and two equivalent Cr4+ atoms to form a mixture of distorted edge and corner-sharing OSr4Cr2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ca2+ and two equivalent Cr4+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sr2+, two equivalent Ca2+, and two equivalent Cr4+ atoms.