Yb2TiO5 crystallizes in the triclinic P1 space group. There are four inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. In the second Yb site, Yb(2) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(5), one O(6), and one O(9) atom. In the third Yb site, Yb(3) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(7), one O(8), and one O(9) atom. In the fourth Yb site, Yb(4) is bonded in a 6-coordinate geometry to one O(10), one O(2), one O(5), one O(6), one O(7), and one O(9) atom. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(10), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 43°. In the second Ti site, Ti(2) is bonded to one O(1), one O(10), one O(4), one O(5), one O(8), and one O(9) atom to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 43°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Yb(1), one Yb(2), one Yb(3), and one Ti(2) atom. In the second O site, O(2) is bonded to one Yb(1), one Yb(2), one Yb(4), and one Ti(1) atom to form distorted OYb3Ti tetrahedra that share  a cornercorner with one O(7)Yb3Ti tetrahedra,  a cornercorner with one O(10)Yb2Ti2 trigonal pyramid,  an edgeedge with one O(7)Yb3Ti tetrahedra,  an edgeedge with one O(9)Yb3Ti tetrahedra,  an edgeedge with one O(10)Yb2Ti2 trigonal pyramid, and  an edgeedge with one O(8)Yb2Ti2 trigonal pyramid. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Yb(1), one Yb(3), and one Ti(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Yb(1), one Yb(3), and one Ti(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Yb(2), one Yb(4), and one Ti(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Yb(2), one Yb(4), and one Ti(1) atom. In the seventh O site, O(7) is bonded to one Yb(1), one Yb(3), one Yb(4), and one Ti(1) atom to form distorted OYb3Ti tetrahedra that share  a cornercorner with one O(2)Yb3Ti tetrahedra, corners with two equivalent O(9)Yb3Ti tetrahedra,  a cornercorner with one O(8)Yb2Ti2 trigonal pyramid,  an edgeedge with one O(2)Yb3Ti tetrahedra,  an edgeedge with one O(10)Yb2Ti2 trigonal pyramid, and  an edgeedge with one O(8)Yb2Ti2 trigonal pyramid. In the eighth O site, O(8) is bonded to one Yb(1), one Yb(3), one Ti(1), and one Ti(2) atom to form distorted OYb2Ti2 trigonal pyramids that share  a cornercorner with one O(7)Yb3Ti tetrahedra, corners with two equivalent O(10)Yb2Ti2 trigonal pyramids,  an edgeedge with one O(2)Yb3Ti tetrahedra,  an edgeedge with one O(7)Yb3Ti tetrahedra, and  an edgeedge with one O(9)Yb3Ti tetrahedra. In the ninth O site, O(9) is bonded to one Yb(2), one Yb(3), one Yb(4), and one Ti(2) atom to form distorted OYb3Ti tetrahedra that share corners with two equivalent O(7)Yb3Ti tetrahedra,  a cornercorner with one O(10)Yb2Ti2 trigonal pyramid,  an edgeedge with one O(2)Yb3Ti tetrahedra,  an edgeedge with one O(10)Yb2Ti2 trigonal pyramid, and  an edgeedge with one O(8)Yb2Ti2 trigonal pyramid. In the tenth O site, O(10) is bonded to one Yb(2), one Yb(4), one Ti(1), and one Ti(2) atom to form distorted OYb2Ti2 trigonal pyramids that share  a cornercorner with one O(2)Yb3Ti tetrahedra,  a cornercorner with one O(9)Yb3Ti tetrahedra, corners with two equivalent O(8)Yb2Ti2 trigonal pyramids,  an edgeedge with one O(2)Yb3Ti tetrahedra,  an edgeedge with one O(7)Yb3Ti tetrahedra, and  an edgeedge with one O(9)Yb3Ti tetrahedra.
Yb2TiO5 crystallizes in the triclinic P1 space group. There are four inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. The Yb(1)-O(1) bond length is 2.26 Å. The Yb(1)-O(2) bond length is 2.25 Å. The Yb(1)-O(3) bond length is 2.34 Å. The Yb(1)-O(4) bond length is 2.26 Å. The Yb(1)-O(7) bond length is 2.48 Å. The Yb(1)-O(8) bond length is 2.43 Å. In the second Yb site, Yb(2) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(5), one O(6), and one O(9) atom. The Yb(2)-O(1) bond length is 2.24 Å. The Yb(2)-O(10) bond length is 2.44 Å. The Yb(2)-O(2) bond length is 2.26 Å. The Yb(2)-O(5) bond length is 2.35 Å. The Yb(2)-O(6) bond length is 2.27 Å. The Yb(2)-O(9) bond length is 2.46 Å. In the third Yb site, Yb(3) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(7), one O(8), and one O(9) atom. The Yb(3)-O(1) bond length is 2.50 Å. The Yb(3)-O(3) bond length is 2.26 Å. The Yb(3)-O(4) bond length is 2.32 Å. The Yb(3)-O(7) bond length is 2.25 Å. The Yb(3)-O(8) bond length is 2.43 Å. The Yb(3)-O(9) bond length is 2.25 Å. In the fourth Yb site, Yb(4) is bonded in a 6-coordinate geometry to one O(10), one O(2), one O(5), one O(6), one O(7), and one O(9) atom. The Yb(4)-O(10) bond length is 2.44 Å. The Yb(4)-O(2) bond length is 2.48 Å. The Yb(4)-O(5) bond length is 2.27 Å. The Yb(4)-O(6) bond length is 2.32 Å. The Yb(4)-O(7) bond length is 2.24 Å. The Yb(4)-O(9) bond length is 2.25 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(10), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 43°. The Ti(1)-O(10) bond length is 2.04 Å. The Ti(1)-O(2) bond length is 1.97 Å. The Ti(1)-O(3) bond length is 1.94 Å. The Ti(1)-O(6) bond length is 1.92 Å. The Ti(1)-O(7) bond length is 1.93 Å. The Ti(1)-O(8) bond length is 2.03 Å. In the second Ti site, Ti(2) is bonded to one O(1), one O(10), one O(4), one O(5), one O(8), and one O(9) atom to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 43°. The Ti(2)-O(1) bond length is 1.97 Å. The Ti(2)-O(10) bond length is 2.01 Å. The Ti(2)-O(4) bond length is 1.89 Å. The Ti(2)-O(5) bond length is 1.97 Å. The Ti(2)-O(8) bond length is 2.06 Å. The Ti(2)-O(9) bond length is 1.93 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Yb(1), one Yb(2), one Yb(3), and one Ti(2) atom. In the second O site, O(2) is bonded to one Yb(1), one Yb(2), one Yb(4), and one Ti(1) atom to form distorted OYb3Ti tetrahedra that share  a cornercorner with one O(7)Yb3Ti tetrahedra,  a cornercorner with one O(10)Yb2Ti2 trigonal pyramid,  an edgeedge with one O(7)Yb3Ti tetrahedra,  an edgeedge with one O(9)Yb3Ti tetrahedra,  an edgeedge with one O(10)Yb2Ti2 trigonal pyramid, and  an edgeedge with one O(8)Yb2Ti2 trigonal pyramid. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Yb(1), one Yb(3), and one Ti(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Yb(1), one Yb(3), and one Ti(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Yb(2), one Yb(4), and one Ti(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Yb(2), one Yb(4), and one Ti(1) atom. In the seventh O site, O(7) is bonded to one Yb(1), one Yb(3), one Yb(4), and one Ti(1) atom to form distorted OYb3Ti tetrahedra that share  a cornercorner with one O(2)Yb3Ti tetrahedra, corners with two equivalent O(9)Yb3Ti tetrahedra,  a cornercorner with one O(8)Yb2Ti2 trigonal pyramid,  an edgeedge with one O(2)Yb3Ti tetrahedra,  an edgeedge with one O(10)Yb2Ti2 trigonal pyramid, and  an edgeedge with one O(8)Yb2Ti2 trigonal pyramid. In the eighth O site, O(8) is bonded to one Yb(1), one Yb(3), one Ti(1), and one Ti(2) atom to form distorted OYb2Ti2 trigonal pyramids that share  a cornercorner with one O(7)Yb3Ti tetrahedra, corners with two equivalent O(10)Yb2Ti2 trigonal pyramids,  an edgeedge with one O(2)Yb3Ti tetrahedra,  an edgeedge with one O(7)Yb3Ti tetrahedra, and  an edgeedge with one O(9)Yb3Ti tetrahedra. In the ninth O site, O(9) is bonded to one Yb(2), one Yb(3), one Yb(4), and one Ti(2) atom to form distorted OYb3Ti tetrahedra that share corners with two equivalent O(7)Yb3Ti tetrahedra,  a cornercorner with one O(10)Yb2Ti2 trigonal pyramid,  an edgeedge with one O(2)Yb3Ti tetrahedra,  an edgeedge with one O(10)Yb2Ti2 trigonal pyramid, and  an edgeedge with one O(8)Yb2Ti2 trigonal pyramid. In the tenth O site, O(10) is bonded to one Yb(2), one Yb(4), one Ti(1), and one Ti(2) atom to form distorted OYb2Ti2 trigonal pyramids that share  a cornercorner with one O(2)Yb3Ti tetrahedra,  a cornercorner with one O(9)Yb3Ti tetrahedra, corners with two equivalent O(8)Yb2Ti2 trigonal pyramids,  an edgeedge with one O(2)Yb3Ti tetrahedra,  an edgeedge with one O(7)Yb3Ti tetrahedra, and  an edgeedge with one O(9)Yb3Ti tetrahedra.