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DOE OSTI · 1707964

Materials Data on Zr3Mn8Si by Materials Project

Abstract

Zr3Mn8Si is Hexagonal Laves-derived structured and crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. there are three inequivalent Zr sites. In the first Zr site, Zr is bonded in a 6-coordinate geometry to one Zr, twelve Mn, and three equivalent Si atoms. The Zr–Zr bond length is 3.05 Å. There are a spread of Zr–Mn bond distances ranging from 2.77–2.86 Å. All Zr–Si bond lengths are 2.96 Å. In the second Zr site, Zr is bonded in a 12-coordinate geometry to four Zr and twelve Mn atoms. All Zr–Zr bond lengths are 3.03 Å. There are a spread of Zr–Mn bond distances ranging from 2.84–2.92 Å. In the third Zr site, Zr is bonded in a 1-coordinate geometry to three equivalent Zr, twelve Mn, and one Si atom. There are a spread of Zr–Mn bond distances ranging from 2.82–3.00 Å. The Zr–Si bond length is 2.87 Å. There are four inequivalent Mn sites. In the first Mn site, Mn is bonded to three equivalent Zr, six Mn, and three equivalent Si atoms to form MnZr3Mn6Si3 cuboctahedra that share corners with twelve MnZr4Mn6Si2 cuboctahedra, edges with six equivalent MnZr3Mn6Si3 cuboctahedra, and faces with twenty MnZr6Mn6 cuboctahedra. There are three shorter (2.41 Å) and three longer (2.48 Å) Mn–Mn bond lengths. All Mn–Si bond lengths are 2.84 Å. In the second Mn site, Mn is bonded to six Zr and six Mn atoms to form MnZr6Mn6 cuboctahedra that share corners with twelve MnZr4Mn6Si2 cuboctahedra, edges with six equivalent MnZr6Mn6 cuboctahedra, and faces with twenty MnZr3Mn6Si3 cuboctahedra. There are three shorter (2.48 Å) and three longer (2.56 Å) Mn–Mn bond lengths. In the third Mn site, Mn is bonded to four Zr, six Mn, and two equivalent Si atoms to form MnZr4Mn6Si2 cuboctahedra that share corners with eighteen MnZr3Mn6Si3 cuboctahedra, edges with six MnZr5Mn6Si cuboctahedra, and faces with eighteen MnZr3Mn6Si3 cuboctahedra. There are two shorter (2.36 Å) and two longer (2.49 Å) Mn–Mn bond lengths. Both Mn–Si bond lengths are 2.82 Å. In the fourth Mn site, Mn is bonded to five Zr, six Mn, and one Si atom to form MnZr5Mn6Si cuboctahedra that share corners with eighteen MnZr3Mn6Si3 cuboctahedra, edges with six MnZr5Mn6Si cuboctahedra, and faces with eighteen MnZr3Mn6Si3 cuboctahedra. There are two shorter (2.31 Å) and two longer (2.54 Å) Mn–Mn bond lengths. The Mn–Si bond length is 2.82 Å. Si is bonded in a 1-coordinate geometry to four Zr and twelve Mn atoms.

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2020-06-05. Materials Data on Zr3Mn8Si by Materials Project. https://doi.org/10.17188/1707964

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