Effect of the position of fluorine substituents in tetrasubstituted metal phthalocyanines on their vibrational spectra

Abstract In this work, the effect of the position of fluorine substituents in tetrafluorosubstituted metal phthalocyanines on their vibrational spectra is studied. For this purpose the assignments of the most intense bands in IR- and Raman spectra of tetrafluorosubstituted metal phthalocyanines with F-substituents in non-peripheral positions MPcF4-np (M = Zn, Co, Cu, Fe, Pd, VO, Pb) were carried out on the basis of the density functional theory (DFT) calculations. The vibrational spectra of MPcF4-np were compared with those of the corresponding derivatives bearing F-substituents in peripheral positions (MPcF4-p). It was shown that similarly to MPcF4-p, the bands in the IR and Raman spectra of MPcF4-np, which are dependent on central metals, are located in the spectral range from 1350 to 1550 cm−1. The effect of the position of fluorine substituents in MPcF4 on the electronic absorption spectra of their solution and films is also discussed.