Fe5Si3 crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 5-coordinate geometry to five equivalent Si(1) atoms. In the second Fe site, Fe(2) is bonded in a 8-coordinate geometry to two equivalent Fe(2) and six equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to four equivalent Fe(2) and five equivalent Fe(1) atoms.
Fe5Si3 crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 5-coordinate geometry to five equivalent Si(1) atoms. There are a spread of Fe(1)-Si(1) bond distances ranging from 2.31-2.57 Å. In the second Fe site, Fe(2) is bonded in a 8-coordinate geometry to two equivalent Fe(2) and six equivalent Si(1) atoms. Both Fe(2)-Fe(2) bond lengths are 2.34 Å. All Fe(2)-Si(1) bond lengths are 2.37 Å. Si(1) is bonded in a 9-coordinate geometry to four equivalent Fe(2) and five equivalent Fe(1) atoms.