YFeO3 crystallizes in the hexagonal P6_3cm space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 7-coordinate geometry to one O(1), three equivalent O(3), and three equivalent O(4) atoms. In the second Y site, Y(2) is bonded to one O(2), three equivalent O(3), and three equivalent O(4) atoms to form distorted YO7 pentagonal bipyramids that share corners with three equivalent Fe(1)O5 trigonal bipyramids and edges with three equivalent Fe(1)O5 trigonal bipyramids. Fe(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form FeO5 trigonal bipyramids that share  a cornercorner with one Y(2)O7 pentagonal bipyramid, corners with six equivalent Fe(1)O5 trigonal bipyramids, and  an edgeedge with one Y(2)O7 pentagonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Y(1) and three equivalent Fe(1) atoms to form OYFe3 trigonal pyramids that share corners with six equivalent O(3)Y3Fe tetrahedra, corners with three equivalent O(1)YFe3 trigonal pyramids, corners with three equivalent O(2)YFe3 trigonal pyramids, and edges with three equivalent O(4)Y3Fe tetrahedra. In the second O site, O(2) is bonded to one Y(2) and three equivalent Fe(1) atoms to form OYFe3 trigonal pyramids that share corners with six equivalent O(4)Y3Fe tetrahedra, corners with six equivalent O(1)YFe3 trigonal pyramids, and edges with three equivalent O(3)Y3Fe tetrahedra. In the third O site, O(3) is bonded to one Y(2), two equivalent Y(1), and one Fe(1) atom to form distorted OY3Fe tetrahedra that share corners with four equivalent O(4)Y3Fe tetrahedra, corners with six equivalent O(3)Y3Fe tetrahedra, corners with four equivalent O(1)YFe3 trigonal pyramids, edges with three equivalent O(4)Y3Fe tetrahedra, and  an edgeedge with one O(2)YFe3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Y(2), two equivalent Y(1), and one Fe(1) atom to form OY3Fe tetrahedra that share corners with four equivalent O(3)Y3Fe tetrahedra, corners with six equivalent O(4)Y3Fe tetrahedra, corners with two equivalent O(2)YFe3 trigonal pyramids, edges with three equivalent O(3)Y3Fe tetrahedra, and edges with two equivalent O(1)YFe3 trigonal pyramids.
YFeO3 crystallizes in the hexagonal P6_3cm space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 7-coordinate geometry to one O(1), three equivalent O(3), and three equivalent O(4) atoms. The Y(1)-O(1) bond length is 2.48 Å. All Y(1)-O(3) bond lengths are 2.31 Å. All Y(1)-O(4) bond lengths are 2.26 Å. In the second Y site, Y(2) is bonded to one O(2), three equivalent O(3), and three equivalent O(4) atoms to form distorted YO7 pentagonal bipyramids that share corners with three equivalent Fe(1)O5 trigonal bipyramids and edges with three equivalent Fe(1)O5 trigonal bipyramids. The Y(2)-O(2) bond length is 2.35 Å. All Y(2)-O(3) bond lengths are 2.31 Å. All Y(2)-O(4) bond lengths are 2.27 Å. Fe(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form FeO5 trigonal bipyramids that share  a cornercorner with one Y(2)O7 pentagonal bipyramid, corners with six equivalent Fe(1)O5 trigonal bipyramids, and  an edgeedge with one Y(2)O7 pentagonal bipyramid. The Fe(1)-O(2) bond length is 2.06 Å. The Fe(1)-O(3) bond length is 1.91 Å. The Fe(1)-O(4) bond length is 1.93 Å. Both Fe(1)-O(1) bond lengths are 2.05 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Y(1) and three equivalent Fe(1) atoms to form OYFe3 trigonal pyramids that share corners with six equivalent O(3)Y3Fe tetrahedra, corners with three equivalent O(1)YFe3 trigonal pyramids, corners with three equivalent O(2)YFe3 trigonal pyramids, and edges with three equivalent O(4)Y3Fe tetrahedra. In the second O site, O(2) is bonded to one Y(2) and three equivalent Fe(1) atoms to form OYFe3 trigonal pyramids that share corners with six equivalent O(4)Y3Fe tetrahedra, corners with six equivalent O(1)YFe3 trigonal pyramids, and edges with three equivalent O(3)Y3Fe tetrahedra. In the third O site, O(3) is bonded to one Y(2), two equivalent Y(1), and one Fe(1) atom to form distorted OY3Fe tetrahedra that share corners with four equivalent O(4)Y3Fe tetrahedra, corners with six equivalent O(3)Y3Fe tetrahedra, corners with four equivalent O(1)YFe3 trigonal pyramids, edges with three equivalent O(4)Y3Fe tetrahedra, and  an edgeedge with one O(2)YFe3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Y(2), two equivalent Y(1), and one Fe(1) atom to form OY3Fe tetrahedra that share corners with four equivalent O(3)Y3Fe tetrahedra, corners with six equivalent O(4)Y3Fe tetrahedra, corners with two equivalent O(2)YFe3 trigonal pyramids, edges with three equivalent O(3)Y3Fe tetrahedra, and edges with two equivalent O(1)YFe3 trigonal pyramids.