Copper- and silver-containing heterometallic iodobismuthates(iii) with 4-(dimethylamino)-1-methylpyridinium cation: structures, thermal stability and optical properties

Reactions of BiI₃, copper or silver iodide and 4-(dimethyl-amino)-1-methylpyridinium iodide [(Me-DMAP)I] result in formation of heterometallic complexes (MeDMAP)₂{[Bi₂Cu₂I₁₀]} and (MeDMAP)₂{[Bi₂Ag₂I₁₀]}. Their crystal structures, thermal stability and optical properties have been studied. Optical band gaps calculated from diffuse reflectance spectroscopy data are 1.81 and 2.06 eV for copper- and silver-containing complexes, respectively.