Materials Data on Ta6Fe7 by Materials Project
Ta6Fe7 is Frank-Kasper $\mu$ Phase structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are three inequivalent Ta sites. In the first Ta site, Ta is bonded in a 6-coordinate geometry to nine Ta and six equivalent Fe atoms. There are a spread of Ta–Ta bond distances ranging from 2.81–3.11 Å. There are three shorter (2.77 Å) and three longer (2.80 Å) Ta–Fe bond lengths. In the second Ta site, Ta is bonded in a 6-coordinate geometry to four Ta and twelve Fe atoms. There are one shorter (2.73 Å) and three longer (2.88 Å) Ta–Ta bond lengths. There are a spread of Ta–Fe bond distances ranging from 2.69–2.94 Å. In the third Ta site, Ta is bonded in a 8-coordinate geometry to eight Ta and six equivalent Fe atoms. The Ta–Ta bond length is 2.66 Å. All Ta–Fe bond lengths are 2.66 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six equivalent Ta and six equivalent Fe atoms to form FeTa6Fe6 cuboctahedra that share corners with twelve equivalent FeTa7Fe5 cuboctahedra, edges with six equivalent FeTa6Fe6 cuboctahedra, and faces with eighteen equivalent FeTa7Fe5 cuboctahedra. All Fe–Fe bond lengths are 2.41 Å. In the second Fe site, Fe is bonded to seven Ta and five Fe atoms to form FeTa7Fe5 cuboctahedra that share corners with fifteen FeTa6Fe6 cuboctahedra, edges with five equivalent FeTa7Fe5 cuboctahedra, and faces with thirteen FeTa6Fe6 cuboctahedra. There are two shorter (2.41 Å) and two longer (2.46 Å) Fe–Fe bond lengths.