Materials Data on BaLa2O4 by Materials Project

Abstract

BaLa2O4 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ba–O bond distances ranging from 2.67–3.14 Å. In the second Ba2+ site, Ba2+ is bonded in a trigonal planar geometry to three O2- atoms. There are one shorter (2.61 Å) and two longer (2.62 Å) Ba–O bond lengths. There are three inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to six O2- atoms to form a mixture of corner and face-sharing LaO6 octahedra. The corner-sharing octahedra tilt angles range from 29–32°. There are a spread of La–O bond distances ranging from 2.36–2.53 Å. In the second La3+ site, La3+ is bonded to six O2- atoms to form a mixture of distorted edge, corner, and face-sharing LaO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of La–O bond distances ranging from 2.29–2.62 Å. In the third La3+ site, La3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of La–O bond distances ranging from 2.35–3.06 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded to four La3+ atoms to form a mixture of distorted edge and corner-sharing OLa4 tetrahedra. In the second O2- site, O2- is bonded to one Ba2+ and three La3+ atoms to form a mixture of distorted edge and corner-sharing OBaLa3 tetrahedra. In the third O2- site, O2- is bonded in a 5-coordinate geometry to three Ba2+ and two equivalent La3+ atoms. In the fourth O2- site, O2- is bonded in a distorted see-saw-like geometry to one Ba2+ and three La3+ atoms. In the fifth O2- site, O2- is bonded to one Ba2+ and three La3+ atoms to form distorted OBaLa3 tetrahedra that share corners with four OLa4 tetrahedra and edges with two OBaLa3 tetrahedra. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to three Ba2+ and two equivalent La3+ atoms. In the seventh O2- site, O2- is bonded in a distorted linear geometry to four La3+ atoms.