Be2CuTl2(O3F4)2 crystallizes in the monoclinic P2_1/c space group. Be(1) is bonded to one F(1), one F(2), one F(3), and one F(4) atom to form BeF4 tetrahedra that share corners with four equivalent Tl(1)OF4 square pyramids. Cu(1) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(3) atoms. Tl(1) is bonded to one O(3), one F(1), one F(2), one F(3), and one F(4) atom to form distorted TlOF4 square pyramids that share corners with four equivalent Be(1)F4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one O(2) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Cu(1) and one O(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cu(1) and one Tl(1) atom. There are four inequivalent F sites. In the first F site, F(4) is bonded in a distorted single-bond geometry to one Be(1) and one Tl(1) atom. In the second F site, F(1) is bonded in a bent 120 degrees geometry to one Be(1) and one Tl(1) atom. In the third F site, F(2) is bonded in a 2-coordinate geometry to one Be(1) and one Tl(1) atom. In the fourth F site, F(3) is bonded in a distorted bent 150 degrees geometry to one Be(1) and one Tl(1) atom.
Be2CuTl2(O3F4)2 crystallizes in the monoclinic P2_1/c space group. Be(1) is bonded to one F(1), one F(2), one F(3), and one F(4) atom to form BeF4 tetrahedra that share corners with four equivalent Tl(1)OF4 square pyramids. The Be(1)-F(1) bond length is 1.68 Å. The Be(1)-F(2) bond length is 1.60 Å. The Be(1)-F(3) bond length is 1.54 Å. The Be(1)-F(4) bond length is 1.53 Å. Cu(1) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(3) atoms. Both Cu(1)-O(2) bond lengths are 2.02 Å. Both Cu(1)-O(3) bond lengths are 1.81 Å. Tl(1) is bonded to one O(3), one F(1), one F(2), one F(3), and one F(4) atom to form distorted TlOF4 square pyramids that share corners with four equivalent Be(1)F4 tetrahedra. The Tl(1)-O(3) bond length is 2.03 Å. The Tl(1)-F(1) bond length is 2.11 Å. The Tl(1)-F(2) bond length is 2.33 Å. The Tl(1)-F(3) bond length is 2.36 Å. The Tl(1)-F(4) bond length is 2.53 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one O(2) atom. The O(1)-O(2) bond length is 1.24 Å. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Cu(1) and one O(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cu(1) and one Tl(1) atom. There are four inequivalent F sites. In the first F site, F(4) is bonded in a distorted single-bond geometry to one Be(1) and one Tl(1) atom. In the second F site, F(1) is bonded in a bent 120 degrees geometry to one Be(1) and one Tl(1) atom. In the third F site, F(2) is bonded in a 2-coordinate geometry to one Be(1) and one Tl(1) atom. In the fourth F site, F(3) is bonded in a distorted bent 150 degrees geometry to one Be(1) and one Tl(1) atom.