FTIR characteristics of halogenated phthalocyanines exhibiting polymorphism

Abstract The infrared spectra of chloroaluminium, chloroindium, bromoindium, dichlorotin and dichloroplatinum phthalocynines have been characterized using FTIR spectroscopy. Assignments have been proposed for many of the absorption peaks and the spectra of new polymorphs of these halogenated phthalocyanines have been compared with well-known α phase materials. The present results indicate that the halogenated materials undergo a phase transition similar to the α → β transition found for the majority of metal phthalocyanines. Distinct differences were found for the two phases of each of the materials studied, particularly in the 700–800 cm -1 region.