Solvothermal synthesis, phase transition and crystal structure of β- and γ-CuPb3Br7

Abstract

Abstract Single crystals of CuPb3Br7 were solvothermally synthesized starting with CuBr and PbBr2 in diethylene glycol at a temperature of 453 K. Two reversible phase transitions were observed with the DSC method at temperatures of 156 K and 433 K. The crystal structures of the low and medium temperature modifications were determined with single crystal X-ray diffraction method. Both modifications can be derived from the Sr7Pt3 type structure and can be differentiated by minor atomic displacements and partial occupation of the additional copper positions.