Materials Data on La2(SnPb)3 by Materials Project

Abstract

La2(PbSn)3 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. La is bonded to six Pb and six Sn atoms to form LaSn6Pb6 cuboctahedra that share corners with twelve equivalent LaSn6Pb6 cuboctahedra, edges with four equivalent SnLa4Pb8 cuboctahedra, edges with twelve PbLa4Sn6Pb2 cuboctahedra, faces with two equivalent SnLa4Pb8 cuboctahedra, faces with six equivalent LaSn6Pb6 cuboctahedra, and faces with six PbLa4Sn6Pb2 cuboctahedra. There are four shorter (3.49 Å) and two longer (3.50 Å) La–Pb bond lengths. There are a spread of La–Sn bond distances ranging from 3.42–3.48 Å. There are two inequivalent Pb sites. In the first Pb site, Pb is bonded to four equivalent La, two equivalent Pb, and six Sn atoms to form distorted PbLa4Sn6Pb2 cuboctahedra that share corners with twelve equivalent PbLa4Sn6Pb2 cuboctahedra, edges with four equivalent PbLa4Sn4Pb4 cuboctahedra, edges with four equivalent SnLa4Pb8 cuboctahedra, edges with eight equivalent LaSn6Pb6 cuboctahedra, faces with two equivalent SnLa4Pb8 cuboctahedra, faces with four equivalent LaSn6Pb6 cuboctahedra, and faces with eight PbLa4Sn6Pb2 cuboctahedra. Both Pb–Pb bond lengths are 3.46 Å. There are a spread of Pb–Sn bond distances ranging from 3.43–3.48 Å. In the second Pb site, Pb is bonded to four equivalent La, four equivalent Pb, and four equivalent Sn atoms to form distorted PbLa4Sn4Pb4 cuboctahedra that share corners with four equivalent PbLa4Sn4Pb4 cuboctahedra, edges with eight equivalent LaSn6Pb6 cuboctahedra, edges with eight equivalent PbLa4Sn6Pb2 cuboctahedra, faces with four equivalent LaSn6Pb6 cuboctahedra, faces with four equivalent SnLa4Pb8 cuboctahedra, and faces with eight PbLa4Sn6Pb2 cuboctahedra. All Pb–Sn bond lengths are 3.49 Å. There are three inequivalent Sn sites. In the first Sn site, Sn is bonded in a 8-coordinate geometry to four equivalent La and four equivalent Pb atoms. In the second Sn site, Sn is bonded to four equivalent La and eight Pb atoms to form SnLa4Pb8 cuboctahedra that share corners with four equivalent SnLa4Pb8 cuboctahedra, edges with eight equivalent LaSn6Pb6 cuboctahedra, edges with eight equivalent PbLa4Sn6Pb2 cuboctahedra, faces with four equivalent LaSn6Pb6 cuboctahedra, faces with four equivalent SnLa4Pb8 cuboctahedra, and faces with eight PbLa4Sn6Pb2 cuboctahedra. In the third Sn site, Sn is bonded in a 8-coordinate geometry to four equivalent La and four equivalent Pb atoms.