Materials Data on Mg7Cr by Materials Project

Dataset · Fri Mar 31 04:00:00 EDT 2017

DOI:https://doi.org/10.17188/1672205· OSTI ID:1672205

Mg7Cr crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are five inequivalent Mg sites. In the first Mg site, Mg is bonded to ten Mg and two equivalent Cr atoms to form MgMg10Cr2 cuboctahedra that share corners with four equivalent CrMg12 cuboctahedra, corners with fourteen MgMg10Cr2 cuboctahedra, edges with two equivalent CrMg12 cuboctahedra, edges with sixteen MgMg10Cr2 cuboctahedra, faces with two equivalent CrMg12 cuboctahedra, and faces with eighteen MgMg10Cr2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.12–3.15 Å. Both Mg–Cr bond lengths are 3.15 Å. In the second Mg site, Mg is bonded to ten Mg and two equivalent Cr atoms to form MgMg10Cr2 cuboctahedra that share corners with four equivalent CrMg12 cuboctahedra, corners with fourteen MgMg10Cr2 cuboctahedra, edges with two equivalent CrMg12 cuboctahedra, edges with sixteen MgMg10Cr2 cuboctahedra, faces with two equivalent CrMg12 cuboctahedra, and faces with eighteen MgMg10Cr2 cuboctahedra. There are two shorter (3.12 Å) and four longer (3.13 Å) Mg–Mg bond lengths. Both Mg–Cr bond lengths are 3.15 Å. In the third Mg site, Mg is bonded to ten Mg and two equivalent Cr atoms to form distorted MgMg10Cr2 cuboctahedra that share corners with eighteen MgMg10Cr2 cuboctahedra, edges with four equivalent CrMg12 cuboctahedra, edges with fourteen MgMg10Cr2 cuboctahedra, faces with two equivalent CrMg12 cuboctahedra, and faces with eighteen MgMg10Cr2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.08–3.21 Å. Both Mg–Cr bond lengths are 3.10 Å. In the fourth Mg site, Mg is bonded to ten Mg and two equivalent Cr atoms to form distorted MgMg10Cr2 cuboctahedra that share corners with eighteen MgMg10Cr2 cuboctahedra, edges with four equivalent CrMg12 cuboctahedra, edges with fourteen MgMg10Cr2 cuboctahedra, faces with two equivalent CrMg12 cuboctahedra, and faces with eighteen MgMg10Cr2 cuboctahedra. There are two shorter (3.13 Å) and two longer (3.15 Å) Mg–Mg bond lengths. Both Mg–Cr bond lengths are 3.10 Å. In the fifth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg10Cr2 cuboctahedra, edges with eighteen MgMg10Cr2 cuboctahedra, faces with six equivalent CrMg12 cuboctahedra, and faces with fourteen MgMg10Cr2 cuboctahedra. Cr is bonded to twelve Mg atoms to form CrMg12 cuboctahedra that share corners with six equivalent CrMg12 cuboctahedra, corners with twelve MgMg10Cr2 cuboctahedra, edges with eighteen MgMg10Cr2 cuboctahedra, faces with two equivalent CrMg12 cuboctahedra, and faces with eighteen MgMg10Cr2 cuboctahedra.

• 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: 1672205
• Report Number(s): mp-1016326
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Cr-Mg
Mg7Cr
crystal structure