Zr6FeSe2 crystallizes in the orthorhombic Pnnm space group. There are six inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a 4-coordinate geometry to two equivalent Fe(1) and two equivalent Se(1) atoms. In the second Zr site, Zr(2) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one Se(2) atom. In the third Zr site, Zr(3) is bonded to two equivalent Fe(1), one Se(1), and two equivalent Se(2) atoms to form distorted edge-sharing ZrFe2Se3 trigonal bipyramids. In the fourth Zr site, Zr(4) is bonded in a 3-coordinate geometry to one Fe(1), one Se(1), and one Se(2) atom. In the fifth Zr site, Zr(5) is bonded in a 3-coordinate geometry to one Fe(1), one Se(1), and two equivalent Se(2) atoms. In the sixth Zr site, Zr(6) is bonded in a 4-coordinate geometry to one Fe(1), two equivalent Se(1), and two equivalent Se(2) atoms. Fe(1) is bonded in a 9-coordinate geometry to one Zr(4), one Zr(5), one Zr(6), two equivalent Zr(1), two equivalent Zr(2), and two equivalent Zr(3) atoms. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded in a 8-coordinate geometry to one Zr(2), one Zr(4), two equivalent Zr(3), two equivalent Zr(5), and two equivalent Zr(6) atoms. In the second Se site, Se(1) is bonded in a 7-coordinate geometry to one Zr(3), one Zr(4), one Zr(5), two equivalent Zr(1), and two equivalent Zr(6) atoms.
Zr6FeSe2 crystallizes in the orthorhombic Pnnm space group. There are six inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a 4-coordinate geometry to two equivalent Fe(1) and two equivalent Se(1) atoms. Both Zr(1)-Fe(1) bond lengths are 2.66 Å. Both Zr(1)-Se(1) bond lengths are 2.85 Å. In the second Zr site, Zr(2) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one Se(2) atom. Both Zr(2)-Fe(1) bond lengths are 2.63 Å. The Zr(2)-Se(2) bond length is 2.96 Å. In the third Zr site, Zr(3) is bonded to two equivalent Fe(1), one Se(1), and two equivalent Se(2) atoms to form distorted edge-sharing ZrFe2Se3 trigonal bipyramids. Both Zr(3)-Fe(1) bond lengths are 2.60 Å. The Zr(3)-Se(1) bond length is 2.83 Å. Both Zr(3)-Se(2) bond lengths are 2.84 Å. In the fourth Zr site, Zr(4) is bonded in a 3-coordinate geometry to one Fe(1), one Se(1), and one Se(2) atom. The Zr(4)-Fe(1) bond length is 3.00 Å. The Zr(4)-Se(1) bond length is 2.87 Å. The Zr(4)-Se(2) bond length is 3.03 Å. In the fifth Zr site, Zr(5) is bonded in a 3-coordinate geometry to one Fe(1), one Se(1), and two equivalent Se(2) atoms. The Zr(5)-Fe(1) bond length is 3.11 Å. The Zr(5)-Se(1) bond length is 2.77 Å. Both Zr(5)-Se(2) bond lengths are 2.80 Å. In the sixth Zr site, Zr(6) is bonded in a 4-coordinate geometry to one Fe(1), two equivalent Se(1), and two equivalent Se(2) atoms. The Zr(6)-Fe(1) bond length is 3.23 Å. Both Zr(6)-Se(1) bond lengths are 2.74 Å. Both Zr(6)-Se(2) bond lengths are 2.74 Å. Fe(1) is bonded in a 9-coordinate geometry to one Zr(4), one Zr(5), one Zr(6), two equivalent Zr(1), two equivalent Zr(2), and two equivalent Zr(3) atoms. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded in a 8-coordinate geometry to one Zr(2), one Zr(4), two equivalent Zr(3), two equivalent Zr(5), and two equivalent Zr(6) atoms. In the second Se site, Se(1) is bonded in a 7-coordinate geometry to one Zr(3), one Zr(4), one Zr(5), two equivalent Zr(1), and two equivalent Zr(6) atoms.