Materials Data on MgSi2 by Materials Project

Dataset · Thu Apr 30 04:00:00 EDT 2020

DOI:https://doi.org/10.17188/1685345· OSTI ID:1685345

MgSi2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to five Si atoms to form distorted MgSi5 tetrahedra that share corners with three equivalent SiSi4 tetrahedra and corners with two equivalent SiMg2Si3 trigonal bipyramids. There are a spread of Mg–Si bond distances ranging from 2.67–3.23 Å. In the second Mg site, Mg is bonded in a 3-coordinate geometry to six Si atoms. There are a spread of Mg–Si bond distances ranging from 2.73–3.17 Å. In the third Mg site, Mg is bonded in a 6-coordinate geometry to six Si atoms. There are a spread of Mg–Si bond distances ranging from 2.65–2.96 Å. In the fourth Mg site, Mg is bonded in a 7-coordinate geometry to seven Si atoms. There are a spread of Mg–Si bond distances ranging from 2.73–3.16 Å. There are eight inequivalent Si sites. In the first Si site, Si is bonded in a 1-coordinate geometry to two Mg and three Si atoms. There are one shorter (2.37 Å) and two longer (2.39 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 8-coordinate geometry to six Mg and two Si atoms. There are one shorter (2.41 Å) and one longer (2.47 Å) Si–Si bond lengths. In the third Si site, Si is bonded in a 8-coordinate geometry to five Mg and three Si atoms. There are one shorter (2.35 Å) and one longer (2.52 Å) Si–Si bond lengths. In the fourth Si site, Si is bonded to two Mg and three Si atoms to form distorted SiMg2Si3 trigonal bipyramids that share corners with two equivalent MgSi5 tetrahedra and corners with two equivalent SiSi4 tetrahedra. There are one shorter (2.36 Å) and one longer (2.37 Å) Si–Si bond lengths. In the fifth Si site, Si is bonded in a 7-coordinate geometry to five Mg and two Si atoms. The Si–Si bond length is 2.45 Å. In the sixth Si site, Si is bonded to four Si atoms to form distorted SiSi4 tetrahedra that share corners with three equivalent MgSi5 tetrahedra and corners with two equivalent SiMg2Si3 trigonal bipyramids. There are one shorter (2.40 Å) and one longer (2.41 Å) Si–Si bond lengths. In the seventh Si site, Si is bonded in a 6-coordinate geometry to two Mg and four Si atoms. The Si–Si bond length is 2.38 Å. In the eighth Si site, Si is bonded in a 5-coordinate geometry to two Mg and three Si atoms.

• 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: 1685345
• Report Number(s): mp-1073298
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Mg-Si
MgSi2
crystal structure