DOI: 10.17188/1734109
title: Materials Data on La2(TlSn)3 by Materials Project

description: La2(TlSn)3 is beta Cu3Ti-derived structured and crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. La is bonded to six Tl and six Sn atoms to form LaTl6Sn6 cuboctahedra that share corners with twelve equivalent LaTl6Sn6 cuboctahedra, edges with twelve TlLa4Tl4Sn4 cuboctahedra, edges with twelve SnLa4Tl6Sn2 cuboctahedra, faces with six equivalent LaTl6Sn6 cuboctahedra, faces with six TlLa4Tl4Sn4 cuboctahedra, and faces with six SnLa4Tl6Sn2 cuboctahedra. There are a spread of La–Tl bond distances ranging from 3.38–3.49 Å. There are two shorter (3.38 Å) and four longer (3.45 Å) La–Sn bond lengths. There are three inequivalent Tl sites. In the first Tl site, Tl is bonded to four equivalent La, four equivalent Tl, and four equivalent Sn atoms to form distorted TlLa4Tl4Sn4 cuboctahedra that share corners with four equivalent TlLa4Tl4Sn4 cuboctahedra, corners with eight equivalent SnLa4Tl4Sn4 cuboctahedra, edges with eight equivalent LaTl6Sn6 cuboctahedra, edges with eight equivalent TlLa4Sn8 cuboctahedra, edges with eight equivalent SnLa4Tl6Sn2 cuboctahedra, faces with four equivalent LaTl6Sn6 cuboctahedra, faces with six SnLa4Tl6Sn2 cuboctahedra, and faces with eight TlLa4Tl4Sn4 cuboctahedra. All Tl–Tl bond lengths are 3.45 Å. All Tl–Sn bond lengths are 3.47 Å. In the second Tl site, Tl is bonded to four equivalent La and eight Sn atoms to form TlLa4Sn8 cuboctahedra that share corners with twelve TlLa4Sn8 cuboctahedra, edges with eight equivalent LaTl6Sn6 cuboctahedra, edges with eight equivalent TlLa4Tl4Sn4 cuboctahedra, edges with eight equivalent SnLa4Tl6Sn2 cuboctahedra, faces with four equivalent LaTl6Sn6 cuboctahedra, faces with six TlLa4Sn8 cuboctahedra, and faces with eight SnLa4Tl6Sn2 cuboctahedra. There are four shorter (3.40 Å) and four longer (3.45 Å) Tl–Sn bond lengths. In the third Tl site, Tl is bonded to four equivalent La, four equivalent Tl, and four equivalent Sn atoms to form distorted TlLa4Tl4Sn4 cuboctahedra that share corners with twelve TlLa4Sn8 cuboctahedra, edges with eight equivalent LaTl6Sn6 cuboctahedra, edges with sixteen SnLa4Tl6Sn2 cuboctahedra, faces with four equivalent LaTl6Sn6 cuboctahedra, faces with four equivalent SnLa4Tl6Sn2 cuboctahedra, and faces with ten TlLa4Tl4Sn4 cuboctahedra. All Tl–Sn bond lengths are 3.47 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded to four equivalent La, six Tl, and two equivalent Sn atoms to form distorted SnLa4Tl6Sn2 cuboctahedra that share corners with twelve equivalent SnLa4Tl6Sn2 cuboctahedra, edges with four equivalent SnLa4Tl4Sn4 cuboctahedra, edges with eight equivalent LaTl6Sn6 cuboctahedra, edges with twelve TlLa4Tl4Sn4 cuboctahedra, faces with four equivalent LaTl6Sn6 cuboctahedra, faces with six TlLa4Tl4Sn4 cuboctahedra, and faces with eight SnLa4Tl6Sn2 cuboctahedra. Both Sn–Sn bond lengths are 3.40 Å. In the second Sn site, Sn is bonded to four equivalent La, four equivalent Tl, and four equivalent Sn atoms to form distorted SnLa4Tl4Sn4 cuboctahedra that share corners with four equivalent SnLa4Tl4Sn4 cuboctahedra, corners with eight equivalent TlLa4Tl4Sn4 cuboctahedra, edges with eight equivalent LaTl6Sn6 cuboctahedra, edges with eight equivalent TlLa4Tl4Sn4 cuboctahedra, edges with eight equivalent SnLa4Tl6Sn2 cuboctahedra, faces with four equivalent LaTl6Sn6 cuboctahedra, faces with six TlLa4Tl4Sn4 cuboctahedra, and faces with eight SnLa4Tl6Sn2 cuboctahedra.