Zr4Fe4Si7 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a 7-coordinate geometry to four equivalent Fe(1), one Si(2), two equivalent Si(1), two equivalent Si(3), and two equivalent Si(4) atoms. In the second Zr site, Zr(2) is bonded in a 7-coordinate geometry to four equivalent Fe(1), two equivalent Si(1), two equivalent Si(3), and three equivalent Si(4) atoms. Fe(1) is bonded to two equivalent Zr(1), two equivalent Zr(2), two equivalent Fe(1), two equivalent Si(2), two equivalent Si(3), and two equivalent Si(4) atoms to form a mixture of distorted edge, face, and corner-sharing FeZr4Fe2Si6 cuboctahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to four equivalent Zr(1), four equivalent Zr(2), and two equivalent Si(1) atoms. In the second Si site, Si(2) is bonded in a 6-coordinate geometry to one Zr(1), four equivalent Fe(1), and one Si(2) atom. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to two equivalent Zr(1), two equivalent Zr(2), and four equivalent Fe(1) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Zr(1), three equivalent Zr(2), and four equivalent Fe(1) atoms.
Zr4Fe4Si7 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a 7-coordinate geometry to four equivalent Fe(1), one Si(2), two equivalent Si(1), two equivalent Si(3), and two equivalent Si(4) atoms. All Zr(1)-Fe(1) bond lengths are 3.07 Å. The Zr(1)-Si(2) bond length is 2.79 Å. Both Zr(1)-Si(1) bond lengths are 2.86 Å. Both Zr(1)-Si(3) bond lengths are 2.83 Å. Both Zr(1)-Si(4) bond lengths are 2.76 Å. In the second Zr site, Zr(2) is bonded in a 7-coordinate geometry to four equivalent Fe(1), two equivalent Si(1), two equivalent Si(3), and three equivalent Si(4) atoms. All Zr(2)-Fe(1) bond lengths are 3.08 Å. Both Zr(2)-Si(1) bond lengths are 2.84 Å. Both Zr(2)-Si(3) bond lengths are 2.78 Å. There is one shorter (2.81 Å) and two longer (2.83 Å) Zr(2)-Si(4) bond lengths. Fe(1) is bonded to two equivalent Zr(1), two equivalent Zr(2), two equivalent Fe(1), two equivalent Si(2), two equivalent Si(3), and two equivalent Si(4) atoms to form a mixture of distorted edge, face, and corner-sharing FeZr4Fe2Si6 cuboctahedra. Both Fe(1)-Fe(1) bond lengths are 2.49 Å. Both Fe(1)-Si(2) bond lengths are 2.42 Å. Both Fe(1)-Si(3) bond lengths are 2.40 Å. Both Fe(1)-Si(4) bond lengths are 2.38 Å. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to four equivalent Zr(1), four equivalent Zr(2), and two equivalent Si(1) atoms. Both Si(1)-Si(1) bond lengths are 2.49 Å. In the second Si site, Si(2) is bonded in a 6-coordinate geometry to one Zr(1), four equivalent Fe(1), and one Si(2) atom. The Si(2)-Si(2) bond length is 2.37 Å. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to two equivalent Zr(1), two equivalent Zr(2), and four equivalent Fe(1) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Zr(1), three equivalent Zr(2), and four equivalent Fe(1) atoms.