Electronic States of the 4,4′-Dinitrobiphenyl–Benzidine Complex

The charge transfer complex composed of 4,4′-dinitrobiphenyl and benzidine was studied by measuring and analyzing the UV crystalline spectra. The deep coloration of this complex was found to be due to the charge transfer bands appearing at 21000 and 25000 cm−1, while the long axes of the component molecules are known to be perpendicular to each other.