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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on La5Si3 by Materials Project

La5Si3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent La+2.40+ sites. In the first La+2.40+ site, La+2.40+ is bonded to six Si4- atoms to form LaSi6 octahedra that share corners with six equivalent LaSi6 octahedra, corners with sixteen equivalent LaSi5 trigonal bipyramids, and faces with eight equivalent LaSi5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 0–58°. There are four shorter (3.24 Å) and two longer (3.47 Å) La–Si bond lengths. In the second La+2.40+ site, La+2.40+ is bonded to five Si4- atoms to form LaSi5 trigonal bipyramids that share corners with four equivalent LaSi6 octahedra, corners with twelve equivalent LaSi5 trigonal bipyramids, edges with seven equivalent LaSi5 trigonal bipyramids, faces with two equivalent LaSi6 octahedra, and a faceface with one LaSi5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 41–64°. There are a spread of La–Si bond distances ranging from 3.13–3.27 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 10-coordinate geometry to ten La+2.40+ atoms. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to eight La+2.40+ and one Si4- atom. The Si–Si bond length is 2.55 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaSi by Materials Project

LaSi crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. La is bonded in a 7-coordinate geometry to seven equivalent Si atoms. There are a spread of La–Si bond distances ranging from 3.15–3.30 Å. Si is bonded in a 9-coordinate geometry to seven equivalent La and two equivalent Si atoms. Both Si–Si bond lengths are 2.52 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaSi2 by Materials Project

LaSi2 is hexagonal omega structure-like structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. La is bonded to twelve equivalent Si atoms to form a mixture of face and edge-sharing LaSi12 cuboctahedra. There are a spread of La–Si bond distances ranging from 3.15–3.30 Å. Si is bonded in a 9-coordinate geometry to six equivalent La and three equivalent Si atoms. There are a spread of Si–Si bond distances ranging from 2.34–2.45 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaSi by Materials Project

LaSi crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent La sites. In the first La site, La is bonded in a 6-coordinate geometry to six equivalent Si atoms. There are four shorter (3.17 Å) and two longer (3.22 Å) La–Si bond lengths. In the second La site, La is bonded in a 8-coordinate geometry to eight equivalent Si atoms. There are four shorter (3.14 Å) and four longer (3.24 Å) La–Si bond lengths. Si is bonded in a 9-coordinate geometry to seven La and two equivalent Si atoms. There are one shorter (2.49 Å) and one longer (2.59 Å) Si–Si bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La5Si3 by Materials Project

La5Si3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent La+2.40+ sites. In the first La+2.40+ site, La+2.40+ is bonded to six equivalent Si4- atoms to form a mixture of corner, edge, and face-sharing LaSi6 octahedra. The corner-sharing octahedral tilt angles are 35°. All La–Si bond lengths are 3.26 Å. In the second La+2.40+ site, La+2.40+ is bonded in a 5-coordinate geometry to five equivalent Si4- atoms. There are a spread of La–Si bond distances ranging from 3.08–3.63 Å. Si4- is bonded in a 9-coordinate geometry to nine La+2.40+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La2Si3 by Materials Project

La2Si3 crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. there are two inequivalent La2+ sites. In the first La2+ site, La2+ is bonded in a 8-coordinate geometry to eight Si+1.33- atoms. There are a spread of La–Si bond distances ranging from 3.12–3.29 Å. In the second La2+ site, La2+ is bonded in a 10-coordinate geometry to ten Si+1.33- atoms. There are a spread of La–Si bond distances ranging from 3.15–3.27 Å. There are three inequivalent Si+1.33- sites. In the first Si+1.33- site, Si+1.33- is bonded in a 7-coordinate geometry to six La2+ and one Si+1.33- atom. The Si–Si bond length is 2.35 Å. In the second Si+1.33- site, Si+1.33- is bonded in a 8-coordinate geometry to six La2+ and two equivalent Si+1.33- atoms. Both Si–Si bond lengths are 2.40 Å. In the third Si+1.33- site, Si+1.33- is bonded in a 9-coordinate geometry to six La2+ and three Si+1.33- atoms.

36 MATERIALS SCIENCE↗