Materials Data on CaLaSi4 by Materials Project

Abstract

CaLaSi4 is hexagonal omega structure-derived structured and crystallizes in the tetragonal I-4m2 space group. The structure is three-dimensional. Ca is bonded to twelve Si atoms to form CaSi12 cuboctahedra that share edges with four equivalent CaSi12 cuboctahedra, edges with eight equivalent LaSi12 cuboctahedra, faces with four equivalent CaSi12 cuboctahedra, and faces with four equivalent LaSi12 cuboctahedra. There are four shorter (3.11 Å) and eight longer (3.30 Å) Ca–Si bond lengths. La is bonded to twelve Si atoms to form LaSi12 cuboctahedra that share edges with four equivalent LaSi12 cuboctahedra, edges with eight equivalent CaSi12 cuboctahedra, faces with four equivalent CaSi12 cuboctahedra, and faces with four equivalent LaSi12 cuboctahedra. There are four shorter (3.11 Å) and eight longer (3.30 Å) La–Si bond lengths. There are four inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to four equivalent Ca, two equivalent La, and three Si atoms. There are one shorter (2.32 Å) and two longer (2.43 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 9-coordinate geometry to two equivalent Ca, four equivalent La, and three Si atoms. The Si–Si bond length is 2.31 Å. In the third Si site, Si is bonded in a 9-coordinate geometry to four equivalent Ca, two equivalent La, and three Si atoms. Both Si–Si bond lengths are 2.43 Å. In the fourth Si site, Si is bonded in a 9-coordinate geometry to four equivalent Ca, two equivalent La, and three Si atoms. All Si–Ca bond lengths are 3.30 Å. Both Si–La bond lengths are 3.11 Å. There are one shorter (2.32 Å) and two longer (2.43 Å) Si–Si bond lengths.