Materials Data on Ca(MnAl3)3 by Materials Project

Abstract

Ca(MnAl3)3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ca is bonded in a 4-coordinate geometry to six Mn and fourteen Al atoms. There are two shorter (3.41 Å) and four longer (3.44 Å) Ca–Mn bond lengths. There are a spread of Ca–Al bond distances ranging from 3.05–3.37 Å. There are two inequivalent Mn sites. In the first Mn site, Mn is bonded to two equivalent Ca and ten Al atoms to form distorted MnCa2Al10 cuboctahedra that share corners with two equivalent AlCa2Mn2Al8 cuboctahedra, corners with eight MnCa2Al10 cuboctahedra, edges with four equivalent MnCa2Mn2Al8 cuboctahedra, faces with two equivalent AlCa2Mn2Al8 cuboctahedra, and faces with four equivalent MnCa2Mn2Al8 cuboctahedra. There are a spread of Mn–Al bond distances ranging from 2.58–2.76 Å. In the second Mn site, Mn is bonded to two equivalent Ca, two equivalent Mn, and eight Al atoms to form distorted MnCa2Mn2Al8 cuboctahedra that share corners with two equivalent AlCa2Mn2Al8 cuboctahedra, corners with eight MnCa2Al10 cuboctahedra, edges with two equivalent MnCa2Al10 cuboctahedra, edges with two equivalent AlCa2Mn2Al8 cuboctahedra, faces with two equivalent AlCa2Mn2Al8 cuboctahedra, and faces with four MnCa2Al10 cuboctahedra. Both Mn–Mn bond lengths are 2.58 Å. There are a spread of Mn–Al bond distances ranging from 2.53–2.68 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to two equivalent Ca, three Mn, and seven Al atoms. There are a spread of Al–Al bond distances ranging from 2.67–2.96 Å. In the second Al site, Al is bonded in a 10-coordinate geometry to one Ca, three Mn, and six Al atoms. There are one shorter (2.78 Å) and one longer (2.83 Å) Al–Al bond lengths. In the third Al site, Al is bonded to two equivalent Ca, two equivalent Mn, and eight Al atoms to form distorted AlCa2Mn2Al8 cuboctahedra that share corners with four equivalent AlCa2Mn2Al8 cuboctahedra, corners with six MnCa2Al10 cuboctahedra, edges with four equivalent MnCa2Mn2Al8 cuboctahedra, and faces with six MnCa2Al10 cuboctahedra.