DOE OSTI2020
Ho2(Fe3Si)3 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 6-coordinate geometry to fourteen Fe and four Si atoms. There are a spread of Ho–Fe bond distances ranging from 2.86–3.24 Å. There are two shorter (2.81 Å) and two longer (2.95 Å) Ho–Si bond lengths. In the second Ho site, Ho is bonded in a 6-coordinate geometry to thirteen Fe and five Si atoms. There are a spread of Ho–Fe bond distances ranging from 2.80–3.23 Å. There are one shorter (2.87 Å) and four longer (2.88 Å) Ho–Si bond lengths. There are five inequivalent Fe sites. In the first Fe site, Fe is bonded in a 12-coordinate geometry to three Ho, six Fe, and three Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.46–2.61 Å. All Fe–Si bond lengths are 2.40 Å. In the second Fe site, Fe is bonded in a 12-coordinate geometry to three Ho, seven Fe, and two equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.39–2.65 Å. Both Fe–Si bond lengths are 2.38 Å. In the third Fe site, Fe is bonded in a 12-coordinate geometry to three Ho, five Fe, and three Si atoms. The Fe–Fe bond length is 2.48 Å. There are one shorter (2.35 Å) and two longer (2.40 Å) Fe–Si bond lengths. In the fourth Fe site, Fe is bonded in a 12-coordinate geometry to three Ho, eight Fe, and one Si atom. There are two shorter (2.39 Å) and one longer (2.54 Å) Fe–Fe bond lengths. The Fe–Si bond length is 2.33 Å. In the fifth Fe site, Fe is bonded in a 9-coordinate geometry to three Ho and six Fe atoms. There are two inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to three Ho and six Fe atoms. In the second Si site, Si is bonded in a 9-coordinate geometry to three Ho and six Fe atoms.