YFe10Mo2 crystallizes in the orthorhombic Immm space group. Y(1) is bonded in a 20-coordinate geometry to two equivalent Mo(1), two equivalent Fe(4), four equivalent Fe(2), four equivalent Fe(3), and eight equivalent Fe(1) atoms. Mo(1) is bonded in a 14-coordinate geometry to one Y(1), one Mo(1), two equivalent Fe(2), two equivalent Fe(3), four equivalent Fe(1), and four equivalent Fe(4) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Y(1), two equivalent Mo(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), and two equivalent Fe(4) atoms to form a mixture of distorted edge, corner, and face-sharing FeY2Fe8Mo2 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Y(1), two equivalent Mo(1), two equivalent Fe(3), two equivalent Fe(4), and four equivalent Fe(1) atoms to form a mixture of distorted edge, corner, and face-sharing FeY2Fe8Mo2 cuboctahedra. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Y(1), two equivalent Mo(1), two equivalent Fe(2), two equivalent Fe(4), and four equivalent Fe(1) atoms. In the fourth Fe site, Fe(4) is bonded in a 14-coordinate geometry to one Y(1), four equivalent Mo(1), one Fe(4), two equivalent Fe(2), two equivalent Fe(3), and four equivalent Fe(1) atoms.
YFe10Mo2 crystallizes in the orthorhombic Immm space group. Y(1) is bonded in a 20-coordinate geometry to two equivalent Mo(1), two equivalent Fe(4), four equivalent Fe(2), four equivalent Fe(3), and eight equivalent Fe(1) atoms. Both Y(1)-Mo(1) bond lengths are 3.08 Å. Both Y(1)-Fe(4) bond lengths are 3.06 Å. All Y(1)-Fe(2) bond lengths are 3.02 Å. All Y(1)-Fe(3) bond lengths are 3.06 Å. All Y(1)-Fe(1) bond lengths are 3.25 Å. Mo(1) is bonded in a 14-coordinate geometry to one Y(1), one Mo(1), two equivalent Fe(2), two equivalent Fe(3), four equivalent Fe(1), and four equivalent Fe(4) atoms. The Mo(1)-Mo(1) bond length is 2.44 Å. Both Mo(1)-Fe(2) bond lengths are 2.69 Å. Both Mo(1)-Fe(3) bond lengths are 2.64 Å. All Mo(1)-Fe(1) bond lengths are 2.61 Å. All Mo(1)-Fe(4) bond lengths are 2.93 Å. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Y(1), two equivalent Mo(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), and two equivalent Fe(4) atoms to form a mixture of distorted edge, corner, and face-sharing FeY2Fe8Mo2 cuboctahedra. Both Fe(1)-Fe(1) bond lengths are 2.38 Å. Both Fe(1)-Fe(2) bond lengths are 2.47 Å. Both Fe(1)-Fe(3) bond lengths are 2.45 Å. Both Fe(1)-Fe(4) bond lengths are 2.63 Å. In the second Fe site, Fe(2) is bonded to two equivalent Y(1), two equivalent Mo(1), two equivalent Fe(3), two equivalent Fe(4), and four equivalent Fe(1) atoms to form a mixture of distorted edge, corner, and face-sharing FeY2Fe8Mo2 cuboctahedra. Both Fe(2)-Fe(3) bond lengths are 2.69 Å. Both Fe(2)-Fe(4) bond lengths are 2.66 Å. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Y(1), two equivalent Mo(1), two equivalent Fe(2), two equivalent Fe(4), and four equivalent Fe(1) atoms. Both Fe(3)-Fe(4) bond lengths are 2.66 Å. In the fourth Fe site, Fe(4) is bonded in a 14-coordinate geometry to one Y(1), four equivalent Mo(1), one Fe(4), two equivalent Fe(2), two equivalent Fe(3), and four equivalent Fe(1) atoms. The Fe(4)-Fe(4) bond length is 2.39 Å.