DOE OSTI2020
CuBrTe crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. there are six inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to four Br1- atoms to form edge-sharing CuBr4 tetrahedra. All Cu–Br bond lengths are 2.49 Å. In the second Cu2+ site, Cu2+ is bonded to four Br1- atoms to form CuBr4 tetrahedra that share corners with four CuTe2Br2 tetrahedra and edges with two CuBr4 tetrahedra. There are two shorter (2.49 Å) and two longer (2.50 Å) Cu–Br bond lengths. In the third Cu2+ site, Cu2+ is bonded to two Te1- and two Br1- atoms to form a mixture of edge and corner-sharing CuTe2Br2 tetrahedra. Both Cu–Te bond lengths are 2.54 Å. There are one shorter (2.53 Å) and one longer (2.55 Å) Cu–Br bond lengths. In the fourth Cu2+ site, Cu2+ is bonded to four equivalent Br1- atoms to form CuBr4 tetrahedra that share corners with four equivalent CuTe2Br2 tetrahedra and edges with two equivalent CuBr4 tetrahedra. All Cu–Br bond lengths are 2.49 Å. In the fifth Cu2+ site, Cu2+ is bonded to two equivalent Te1- and two equivalent Br1- atoms to form a mixture of edge and corner-sharing CuTe2Br2 tetrahedra. Both Cu–Te bond lengths are 2.54 Å. Both Cu–Br bond lengths are 2.54 Å. In the sixth Cu2+ site, Cu2+ is bonded to four equivalent Br1- atoms to form edge-sharing CuBr4 tetrahedra. All Cu–Br bond lengths are 2.49 Å. There are three inequivalent Te1- sites. In the first Te1- site, Te1- is bonded in a 1-coordinate geometry to one Cu2+, two Te1-, and two Br1- atoms. There are one shorter (2.80 Å) and one longer (2.89 Å) Te–Te bond lengths. There are one shorter (3.56 Å) and one longer (3.58 Å) Te–Br bond lengths. In the second Te1- site, Te1- is bonded in a 1-coordinate geometry to one Cu2+, two Te1-, and two Br1- atoms. There are one shorter (2.80 Å) and one longer (2.89 Å) Te–Te bond lengths. Both Te–Br bond lengths are 3.59 Å. In the third Te1- site, Te1- is bonded in a 1-coordinate geometry to one Cu2+, two Te1-, and two equivalent Br1- atoms. There are one shorter (3.57 Å) and one longer (3.62 Å) Te–Br bond lengths. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 3-coordinate geometry to three Cu2+ and two equivalent Te1- atoms. In the second Br1- site, Br1- is bonded in a 3-coordinate geometry to three Cu2+ and two Te1- atoms. In the third Br1- site, Br1- is bonded in a 3-coordinate geometry to three Cu2+ and two Te1- atoms.