Fe2Si is Tungsten-derived structured and crystallizes in the tetragonal P4/mmm space group. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted body-centered cubic geometry to four equivalent Fe(3) and four equivalent Si(1) atoms. In the second Fe site, Fe(2) is bonded in a body-centered cubic geometry to eight equivalent Si(1) atoms. In the third Fe site, Fe(3) is bonded in a 14-coordinate geometry to four equivalent Fe(3), eight equivalent Fe(1), and two equivalent Si(1) atoms. Si(1) is bonded in a distorted body-centered cubic geometry to one Fe(3), four equivalent Fe(1), and four equivalent Fe(2) atoms.
Fe2Si is Tungsten-derived structured and crystallizes in the tetragonal P4/mmm space group. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted body-centered cubic geometry to four equivalent Fe(3) and four equivalent Si(1) atoms. All Fe(1)-Fe(3) bond lengths are 2.45 Å. All Fe(1)-Si(1) bond lengths are 2.38 Å. In the second Fe site, Fe(2) is bonded in a body-centered cubic geometry to eight equivalent Si(1) atoms. All Fe(2)-Si(1) bond lengths are 2.42 Å. In the third Fe site, Fe(3) is bonded in a 14-coordinate geometry to four equivalent Fe(3), eight equivalent Fe(1), and two equivalent Si(1) atoms. All Fe(3)-Fe(3) bond lengths are 2.80 Å. Both Fe(3)-Si(1) bond lengths are 2.77 Å. Si(1) is bonded in a distorted body-centered cubic geometry to one Fe(3), four equivalent Fe(1), and four equivalent Fe(2) atoms.