Materials Data on LaCrSe2O by Materials Project

Abstract

LaCrOSe2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. La3+ is bonded in a 3-coordinate geometry to three equivalent Se2- and three equivalent O2- atoms. All La–Se bond lengths are 3.23 Å. There are two shorter (2.38 Å) and one longer (2.46 Å) La–O bond lengths. There are two inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to four equivalent Se2- and two equivalent O2- atoms to form distorted CrSe4O2 octahedra that share corners with four equivalent CrSe6 octahedra and edges with two equivalent CrSe4O2 octahedra. The corner-sharing octahedral tilt angles are 55°. All Cr–Se bond lengths are 2.64 Å. Both Cr–O bond lengths are 2.04 Å. In the second Cr3+ site, Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with four equivalent CrSe4O2 octahedra and edges with two equivalent CrSe6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are four shorter (2.59 Å) and two longer (2.60 Å) Cr–Se bond lengths. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 2-coordinate geometry to three equivalent La3+ and two equivalent Cr3+ atoms. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to three Cr3+ atoms. O2- is bonded to three equivalent La3+ and one Cr3+ atom to form a mixture of corner and edge-sharing OLa3Cr tetrahedra.