Materials Data on La3As2BrO7 by Materials Project

Abstract

La3As2O7Br crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are two shorter (2.41 Å) and four longer (2.49 Å) La–O bond lengths. In the second La3+ site, La3+ is bonded in a 9-coordinate geometry to eight O2- and one Br1- atom. There are a spread of La–O bond distances ranging from 2.38–3.02 Å. The La–Br bond length is 3.14 Å. As3+ is bonded in a distorted T-shaped geometry to three O2- atoms. There is one shorter (1.79 Å) and two longer (1.83 Å) As–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one As3+ atom. In the second O2- site, O2- is bonded to four equivalent La3+ atoms to form edge-sharing OLa4 tetrahedra. In the third O2- site, O2- is bonded in a 2-coordinate geometry to three La3+ and one As3+ atom. Br1- is bonded in a 2-coordinate geometry to two equivalent La3+ atoms.