Materials Data on LaNb2CuBrO7 by Materials Project

Abstract

LaNb2CuO7Br is Pb(Zr_(1-x)Ti_x)O3-derived structured and crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. La3+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of La–O bond distances ranging from 2.45–2.85 Å. Nb5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.81–2.27 Å. Cu2+ is bonded in a 2-coordinate geometry to two equivalent O2- and two equivalent Br1- atoms. Both Cu–O bond lengths are 1.87 Å. There are one shorter (2.51 Å) and one longer (2.52 Å) Cu–Br bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent La3+ and two equivalent Nb5+ atoms to form a mixture of distorted edge and corner-sharing OLa2Nb2 trigonal pyramids. In the second O2- site, O2- is bonded in a linear geometry to one Nb5+ and one Cu2+ atom. In the third O2- site, O2- is bonded to two equivalent La3+ and two equivalent Nb5+ atoms to form a mixture of distorted edge and corner-sharing OLa2Nb2 tetrahedra. In the fourth O2- site, O2- is bonded in a linear geometry to two equivalent La3+ and two equivalent Nb5+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent La3+ and two equivalent Nb5+ atoms. Br1- is bonded in a 2-coordinate geometry to two equivalent Cu2+ atoms.