DOI: 10.17188/1707611
title: Materials Data on UMnAl by Materials Project

description: UMnAl is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are two inequivalent U sites. In the first U site, U is bonded in a 6-coordinate geometry to three equivalent U, five Mn, and seven Al atoms. There are a spread of U–U bond distances ranging from 2.83–3.20 Å. There are a spread of U–Mn bond distances ranging from 2.81–3.04 Å. There are a spread of U–Al bond distances ranging from 2.97–3.25 Å. In the second U site, U is bonded in a 4-coordinate geometry to four U, seven Mn, and five Al atoms. The U–U bond length is 3.26 Å. There are a spread of U–Mn bond distances ranging from 2.99–3.08 Å. There are a spread of U–Al bond distances ranging from 3.07–3.17 Å. There are three inequivalent Mn sites. In the first Mn site, Mn is bonded to six U, four Mn, and two equivalent Al atoms to form MnU6Mn4Al2 cuboctahedra that share corners with eight MnU6Mn4Al2 cuboctahedra, corners with ten AlU6Mn2Al4 cuboctahedra, edges with two equivalent MnU6Mn4Al2 cuboctahedra, edges with four equivalent AlU6Mn2Al4 cuboctahedra, faces with eight AlU6Mn2Al4 cuboctahedra, and faces with ten MnU6Mn4Al2 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.57–2.68 Å. There are one shorter (2.53 Å) and one longer (2.57 Å) Mn–Al bond lengths. In the second Mn site, Mn is bonded to six U, four Mn, and two equivalent Al atoms to form MnU6Mn4Al2 cuboctahedra that share corners with eight MnU6Mn4Al2 cuboctahedra, corners with ten AlU6Mn2Al4 cuboctahedra, edges with two equivalent MnU6Mn4Al2 cuboctahedra, edges with four equivalent AlU6Mn2Al4 cuboctahedra, faces with eight AlU6Mn2Al4 cuboctahedra, and faces with ten MnU6Mn4Al2 cuboctahedra. Both Mn–Mn bond lengths are 2.68 Å. There are one shorter (2.53 Å) and one longer (2.57 Å) Mn–Al bond lengths. In the third Mn site, Mn is bonded to six U, two Mn, and four Al atoms to form MnU6Mn2Al4 cuboctahedra that share corners with four MnU6Mn4Al2 cuboctahedra, corners with eight AlU6Mn2Al4 cuboctahedra, edges with six equivalent MnU6Mn2Al4 cuboctahedra, faces with eight MnU6Mn4Al2 cuboctahedra, and faces with twelve AlU6Mn2Al4 cuboctahedra. There are a spread of Mn–Al bond distances ranging from 2.57–2.64 Å. There are four inequivalent Al sites. In the first Al site, Al is bonded to six U, two equivalent Mn, and four Al atoms to form AlU6Mn2Al4 cuboctahedra that share corners with six AlU6Mn2Al4 cuboctahedra, corners with twelve MnU6Mn4Al2 cuboctahedra, edges with six AlU6Mn2Al4 cuboctahedra, faces with eight AlU6Mn2Al4 cuboctahedra, and faces with ten MnU6Mn4Al2 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.53–2.57 Å. In the second Al site, Al is bonded to six U, two equivalent Mn, and four Al atoms to form AlU6Mn2Al4 cuboctahedra that share corners with eight AlU6Mn2Al4 cuboctahedra, corners with ten MnU6Mn4Al2 cuboctahedra, edges with two equivalent AlU6Mn2Al4 cuboctahedra, edges with four equivalent MnU6Mn4Al2 cuboctahedra, faces with eight MnU6Mn4Al2 cuboctahedra, and faces with ten AlU6Mn2Al4 cuboctahedra. There are one shorter (2.56 Å) and one longer (2.64 Å) Al–Al bond lengths. In the third Al site, Al is bonded to six U, two equivalent Mn, and four Al atoms to form AlU6Mn2Al4 cuboctahedra that share corners with eight AlU6Mn2Al4 cuboctahedra, corners with ten MnU6Mn4Al2 cuboctahedra, edges with two equivalent AlU6Mn2Al4 cuboctahedra, edges with four equivalent MnU6Mn4Al2 cuboctahedra, faces with eight MnU6Mn4Al2 cuboctahedra, and faces with ten AlU6Mn2Al4 cuboctahedra. In the fourth Al site, Al is bonded to six U and six Mn atoms to form AlU6Mn6 cuboctahedra that share corners with four equivalent MnU6Mn2Al4 cuboctahedra, corners with fourteen AlU6Mn2Al4 cuboctahedra, edges with six AlU6Mn2Al4 cuboctahedra, faces with four AlU6Mn2Al4 cuboctahedra, and faces with fourteen MnU6Mn4Al2 cuboctahedra.