Molecular organization in the thin films of chloroaluminium hexadecafluorophthalocyanine revealed by polarized Raman spectroscopy

摘要

The molecular arrangement in the thin films of chloroaluminium hexadecafluorophthalocyanine (AlClPcF_(16)) grown by physical vapor deposition has been studied using atomic force microscopy and optical spectroscopy techniques. It was shown that AlClPcF_(16) films, 20 nm thick, prepared on the quartz substrate at 60 ℃ are well organized and characterized by a predominantly co-facial parallel arrangement of molecules vertical to the surface. According to the polarized Raman spectroscopy measurements, the mean tilt angle between the AlClPcF_(16) species and the substrate surface was found to be 75 ± 5°. All intense bands in the experimental Infrared and Raman spectra of AlClPcF_(16) were assigned using density functional theory calculations. The theoretically predicted geometry and wavenumbers are in a good agreement with the experimental values. Apart from this, the temperature dependence of vapor pressure and sublimation enthalpy of AlClPcF_(16) were determined by the Knudsen effusion method.