Tm2ReC2 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to two equivalent C(1) and three equivalent C(2) atoms to form a mixture of edge and corner-sharing TmC5 square pyramids. In the second Tm site, Tm(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent C(1) and two equivalent C(2) atoms. Re(1) is bonded in a distorted trigonal planar geometry to one C(2) and two equivalent C(1) atoms. There are two inequivalent C sites. In the first C site, C(1) is bonded to two equivalent Tm(1), two equivalent Tm(2), and two equivalent Re(1) atoms to form CTm4Re2 octahedra that share corners with two equivalent C(1)Tm4Re2 octahedra, corners with two equivalent C(2)Tm5Re octahedra, edges with two equivalent C(1)Tm4Re2 octahedra, and edges with five equivalent C(2)Tm5Re octahedra. The corner-sharing octahedral tilt angles range from 10-39°. In the second C site, C(2) is bonded to two equivalent Tm(2), three equivalent Tm(1), and one Re(1) atom to form CTm5Re octahedra that share corners with two equivalent C(1)Tm4Re2 octahedra, corners with four equivalent C(2)Tm5Re octahedra, edges with two equivalent C(2)Tm5Re octahedra, and edges with five equivalent C(1)Tm4Re2 octahedra. The corner-sharing octahedral tilt angles range from 3-39°.
Tm2ReC2 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to two equivalent C(1) and three equivalent C(2) atoms to form a mixture of edge and corner-sharing TmC5 square pyramids. There is one shorter (2.46 Å) and one longer (2.54 Å) Tm(1)-C(1) bond length. There are two shorter (2.52 Å) and one longer (2.55 Å) Tm(1)-C(2) bond length. In the second Tm site, Tm(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent C(1) and two equivalent C(2) atoms. Both Tm(2)-C(1) bond lengths are 2.53 Å. There is one shorter (2.50 Å) and one longer (2.59 Å) Tm(2)-C(2) bond length. Re(1) is bonded in a distorted trigonal planar geometry to one C(2) and two equivalent C(1) atoms. The Re(1)-C(2) bond length is 1.93 Å. There is one shorter (1.97 Å) and one longer (2.02 Å) Re(1)-C(1) bond length. There are two inequivalent C sites. In the first C site, C(1) is bonded to two equivalent Tm(1), two equivalent Tm(2), and two equivalent Re(1) atoms to form CTm4Re2 octahedra that share corners with two equivalent C(1)Tm4Re2 octahedra, corners with two equivalent C(2)Tm5Re octahedra, edges with two equivalent C(1)Tm4Re2 octahedra, and edges with five equivalent C(2)Tm5Re octahedra. The corner-sharing octahedral tilt angles range from 10-39°. In the second C site, C(2) is bonded to two equivalent Tm(2), three equivalent Tm(1), and one Re(1) atom to form CTm5Re octahedra that share corners with two equivalent C(1)Tm4Re2 octahedra, corners with four equivalent C(2)Tm5Re octahedra, edges with two equivalent C(2)Tm5Re octahedra, and edges with five equivalent C(1)Tm4Re2 octahedra. The corner-sharing octahedral tilt angles range from 3-39°.