Tm2Cu2O5 is Spinel-like structured and crystallizes in the orthorhombic Pna2_1 space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(5) atoms to form a mixture of distorted edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 20-64°. In the second Tm site, Tm(2) is bonded to one O(3), one O(5), two equivalent O(1), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 20-64°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a rectangular see-saw-like geometry to one O(2), one O(3), one O(4), and one O(5) atom. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are five inequivalent O sites. In the first O site, O(5) is bonded to one Tm(2), two equivalent Tm(1), and one Cu(1) atom to form OTm3Cu tetrahedra that share corners with two equivalent O(5)Tm3Cu tetrahedra, corners with four equivalent O(1)Tm3Cu tetrahedra, corners with three equivalent O(2)Tm2Cu2 trigonal pyramids, corners with three equivalent O(4)Tm2Cu2 trigonal pyramids, and  an edgeedge with one O(2)Tm2Cu2 trigonal pyramid. In the second O site, O(1) is bonded to one Tm(1), two equivalent Tm(2), and one Cu(2) atom to form OTm3Cu tetrahedra that share corners with two equivalent O(1)Tm3Cu tetrahedra, corners with four equivalent O(5)Tm3Cu tetrahedra, corners with three equivalent O(2)Tm2Cu2 trigonal pyramids, corners with three equivalent O(4)Tm2Cu2 trigonal pyramids, and  an edgeedge with one O(4)Tm2Cu2 trigonal pyramid. In the third O site, O(2) is bonded to two equivalent Tm(1), one Cu(1), and one Cu(2) atom to form distorted OTm2Cu2 trigonal pyramids that share corners with three equivalent O(1)Tm3Cu tetrahedra, corners with three equivalent O(5)Tm3Cu tetrahedra, corners with two equivalent O(2)Tm2Cu2 trigonal pyramids,  an edgeedge with one O(5)Tm3Cu tetrahedra, and  an edgeedge with one O(4)Tm2Cu2 trigonal pyramid. In the fourth O site, O(3) is bonded in a distorted see-saw-like geometry to one Tm(1), one Tm(2), one Cu(1), and one Cu(2) atom. In the fifth O site, O(4) is bonded to two equivalent Tm(2), one Cu(1), and one Cu(2) atom to form OTm2Cu2 trigonal pyramids that share corners with three equivalent O(1)Tm3Cu tetrahedra, corners with three equivalent O(5)Tm3Cu tetrahedra, corners with two equivalent O(4)Tm2Cu2 trigonal pyramids,  an edgeedge with one O(1)Tm3Cu tetrahedra, and  an edgeedge with one O(2)Tm2Cu2 trigonal pyramid.
Tm2Cu2O5 is Spinel-like structured and crystallizes in the orthorhombic Pna2_1 space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(5) atoms to form a mixture of distorted edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 20-64°. The Tm(1)-O(1) bond length is 2.20 Å. The Tm(1)-O(3) bond length is 2.26 Å. Both Tm(1)-O(2) bond lengths are 2.27 Å. Both Tm(1)-O(5) bond lengths are 2.26 Å. In the second Tm site, Tm(2) is bonded to one O(3), one O(5), two equivalent O(1), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 20-64°. The Tm(2)-O(3) bond length is 2.26 Å. The Tm(2)-O(5) bond length is 2.20 Å. There is one shorter (2.25 Å) and one longer (2.27 Å) Tm(2)-O(1) bond length. There is one shorter (2.26 Å) and one longer (2.28 Å) Tm(2)-O(4) bond length. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a rectangular see-saw-like geometry to one O(2), one O(3), one O(4), and one O(5) atom. The Cu(1)-O(2) bond length is 1.94 Å. The Cu(1)-O(3) bond length is 1.97 Å. The Cu(1)-O(4) bond length is 2.02 Å. The Cu(1)-O(5) bond length is 2.00 Å. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. The Cu(2)-O(1) bond length is 2.00 Å. The Cu(2)-O(2) bond length is 2.01 Å. The Cu(2)-O(3) bond length is 1.97 Å. The Cu(2)-O(4) bond length is 1.94 Å. There are five inequivalent O sites. In the first O site, O(5) is bonded to one Tm(2), two equivalent Tm(1), and one Cu(1) atom to form OTm3Cu tetrahedra that share corners with two equivalent O(5)Tm3Cu tetrahedra, corners with four equivalent O(1)Tm3Cu tetrahedra, corners with three equivalent O(2)Tm2Cu2 trigonal pyramids, corners with three equivalent O(4)Tm2Cu2 trigonal pyramids, and  an edgeedge with one O(2)Tm2Cu2 trigonal pyramid. In the second O site, O(1) is bonded to one Tm(1), two equivalent Tm(2), and one Cu(2) atom to form OTm3Cu tetrahedra that share corners with two equivalent O(1)Tm3Cu tetrahedra, corners with four equivalent O(5)Tm3Cu tetrahedra, corners with three equivalent O(2)Tm2Cu2 trigonal pyramids, corners with three equivalent O(4)Tm2Cu2 trigonal pyramids, and  an edgeedge with one O(4)Tm2Cu2 trigonal pyramid. In the third O site, O(2) is bonded to two equivalent Tm(1), one Cu(1), and one Cu(2) atom to form distorted OTm2Cu2 trigonal pyramids that share corners with three equivalent O(1)Tm3Cu tetrahedra, corners with three equivalent O(5)Tm3Cu tetrahedra, corners with two equivalent O(2)Tm2Cu2 trigonal pyramids,  an edgeedge with one O(5)Tm3Cu tetrahedra, and  an edgeedge with one O(4)Tm2Cu2 trigonal pyramid. In the fourth O site, O(3) is bonded in a distorted see-saw-like geometry to one Tm(1), one Tm(2), one Cu(1), and one Cu(2) atom. In the fifth O site, O(4) is bonded to two equivalent Tm(2), one Cu(1), and one Cu(2) atom to form OTm2Cu2 trigonal pyramids that share corners with three equivalent O(1)Tm3Cu tetrahedra, corners with three equivalent O(5)Tm3Cu tetrahedra, corners with two equivalent O(4)Tm2Cu2 trigonal pyramids,  an edgeedge with one O(1)Tm3Cu tetrahedra, and  an edgeedge with one O(2)Tm2Cu2 trigonal pyramid.