Materials Data on Ti21Mn25 by Materials Project

Abstract

Ti21Mn25 is Frank-Kasper $\mu$ Phase-like structured and crystallizes in the trigonal R-3c space group. The structure is three-dimensional. there are four inequivalent Ti sites. In the first Ti site, Ti is bonded in a 12-coordinate geometry to eight Ti and four Mn atoms. There are a spread of Ti–Ti bond distances ranging from 2.85–2.93 Å. There are two shorter (2.62 Å) and two longer (2.67 Å) Ti–Mn bond lengths. In the second Ti site, Ti is bonded in a 12-coordinate geometry to seven Ti and seven Mn atoms. There are a spread of Ti–Ti bond distances ranging from 2.78–3.22 Å. There are a spread of Ti–Mn bond distances ranging from 2.64–2.78 Å. In the third Ti site, Ti is bonded in a 12-coordinate geometry to four Ti and twelve Mn atoms. There are two shorter (2.87 Å) and one longer (2.91 Å) Ti–Ti bond lengths. There are a spread of Ti–Mn bond distances ranging from 2.73–2.88 Å. In the fourth Ti site, Ti is bonded in a 12-coordinate geometry to six Ti and eight Mn atoms. There are one shorter (2.67 Å) and one longer (2.79 Å) Ti–Ti bond lengths. There are a spread of Ti–Mn bond distances ranging from 2.65–2.94 Å. There are six inequivalent Mn sites. In the first Mn site, Mn is bonded to six equivalent Ti and six Mn atoms to form MnTi6Mn6 cuboctahedra that share corners with twelve MnTi6Mn6 cuboctahedra, edges with four equivalent MnTi7Mn5 cuboctahedra, and faces with sixteen MnTi6Mn6 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.34–2.47 Å. In the second Mn site, Mn is bonded to seven Ti and five Mn atoms to form a mixture of edge, face, and corner-sharing MnTi7Mn5 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.39–2.44 Å. In the third Mn site, Mn is bonded to eight Ti and four Mn atoms to form MnTi8Mn4 cuboctahedra that share corners with eight MnTi7Mn5 cuboctahedra, edges with two equivalent MnTi8Mn4 cuboctahedra, and faces with eight MnTi7Mn5 cuboctahedra. Both Mn–Mn bond lengths are 2.42 Å. In the fourth Mn site, Mn is bonded to seven Ti and five Mn atoms to form distorted MnTi7Mn5 cuboctahedra that share corners with eleven MnTi6Mn6 cuboctahedra, edges with three MnTi7Mn5 cuboctahedra, and faces with thirteen MnTi6Mn6 cuboctahedra. Both Mn–Mn bond lengths are 2.35 Å. In the fifth Mn site, Mn is bonded in a 12-coordinate geometry to seven Ti and five Mn atoms. The Mn–Mn bond length is 2.37 Å. In the sixth Mn site, Mn is bonded to six equivalent Ti and six equivalent Mn atoms to form MnTi6Mn6 cuboctahedra that share edges with six equivalent MnTi7Mn5 cuboctahedra and faces with twenty MnTi6Mn6 cuboctahedra.