Materials Data on CaLa3Si8 by Materials Project

Dataset · Sun May 03 04:00:00 EDT 2020

DOI:https://doi.org/10.17188/1678095· OSTI ID:1678095

CaLa3Si8 is hexagonal omega structure-derived structured and crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. Ca2+ is bonded to twelve Si1- atoms to form CaSi12 cuboctahedra that share edges with four equivalent CaSi12 cuboctahedra, edges with eight LaSi12 cuboctahedra, faces with four equivalent CaSi12 cuboctahedra, and faces with four LaSi12 cuboctahedra. There are four shorter (3.16 Å) and eight longer (3.24 Å) Ca–Si bond lengths. There are three inequivalent La2+ sites. In the first La2+ site, La2+ is bonded to twelve Si1- atoms to form a mixture of edge and face-sharing LaSi12 cuboctahedra. There are four shorter (3.18 Å) and eight longer (3.24 Å) La–Si bond lengths. In the second La2+ site, La2+ is bonded to twelve Si1- atoms to form LaSi12 cuboctahedra that share edges with four equivalent CaSi12 cuboctahedra, edges with eight LaSi12 cuboctahedra, faces with two equivalent CaSi12 cuboctahedra, and faces with six LaSi12 cuboctahedra. There are a spread of La–Si bond distances ranging from 3.17–3.24 Å. In the third La2+ site, La2+ is bonded to twelve Si1- atoms to form LaSi12 cuboctahedra that share edges with four equivalent CaSi12 cuboctahedra, edges with eight LaSi12 cuboctahedra, faces with two equivalent CaSi12 cuboctahedra, and faces with six LaSi12 cuboctahedra. There are a spread of La–Si bond distances ranging from 3.17–3.24 Å. There are six inequivalent Si1- sites. In the first Si1- site, Si1- is bonded in a 9-coordinate geometry to four equivalent Ca2+, two equivalent La2+, and three Si1- atoms. There are one shorter (2.36 Å) and two longer (2.42 Å) Si–Si bond lengths. In the second Si1- site, Si1- is bonded in a 9-coordinate geometry to six La2+ and three Si1- atoms. There are one shorter (2.39 Å) and two longer (2.43 Å) Si–Si bond lengths. In the third Si1- site, Si1- is bonded in a 9-coordinate geometry to two equivalent Ca2+, four equivalent La2+, and three Si1- atoms. The Si–Si bond length is 2.39 Å. In the fourth Si1- site, Si1- is bonded in a 9-coordinate geometry to six La2+ and three Si1- atoms. The Si–Si bond length is 2.39 Å. In the fifth Si1- site, Si1- is bonded in a 9-coordinate geometry to four equivalent Ca2+, two equivalent La2+, and three Si1- atoms. Both Si–Si bond lengths are 2.42 Å. In the sixth Si1- site, Si1- is bonded in a 9-coordinate geometry to six La2+ and three Si1- atoms. Both Si–Si bond lengths are 2.43 Å.

• Research Organization: LBNL Materials Project; Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Contributing Organization: The Materials Project; MIT; UC Berkeley; Duke; U Louvain
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 1678095
• Report Number(s): mp-1227076
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Ca-La-Si
CaLa3Si8
crystal structure