Materials Data on LaCu9Sn4 by Materials Project

Abstract

LaCu9Sn4 is Bergman Structure: Mg32(Al,Zn)49 Bergman-like structured and crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. La is bonded in a 8-coordinate geometry to sixteen Cu and eight equivalent Sn atoms. There are eight shorter (3.58 Å) and eight longer (3.80 Å) La–Cu bond lengths. All La–Sn bond lengths are 3.56 Å. There are three inequivalent Cu sites. In the first Cu site, Cu is bonded in a 1-coordinate geometry to two equivalent La, seven Cu, and four equivalent Sn atoms. There are a spread of Cu–Cu bond distances ranging from 2.42–3.14 Å. There are two shorter (2.82 Å) and two longer (2.86 Å) Cu–Sn bond lengths. In the second Cu site, Cu is bonded in a distorted cuboctahedral geometry to eight Cu and four equivalent Sn atoms. All Cu–Cu bond lengths are 2.51 Å. All Cu–Sn bond lengths are 2.62 Å. In the third Cu site, Cu is bonded in a 12-coordinate geometry to two equivalent La, eight Cu, and two equivalent Sn atoms. There are two shorter (2.53 Å) and one longer (2.74 Å) Cu–Cu bond lengths. Both Cu–Sn bond lengths are 2.70 Å. Sn is bonded in a 12-coordinate geometry to two equivalent La, seven Cu, and three equivalent Sn atoms. There are two shorter (2.87 Å) and one longer (3.00 Å) Sn–Sn bond lengths.