The molecular arrangement and phase transitions in the vanadyl hexadecafluorophthalocyanine (VOPcF 16 ) thin films grown by physical vapor deposition have been studied using in situ X-ray diffraction, atomic force microscopy, and optical spectroscopy techniques (UV, IR, and Raman). The complete transition from the low-temperature linear cofacial structure to the slipped dimeric one occurs in the temperature range 160−220 °C. This conversion was found to be irreversible upon cooling the VOPcF 16 film back to 20 °C. The structural transformation leads to decrease of the in-plane conductivity of the film by 2 orders of magnitude. According to the polarized Raman spectroscopy measurements, the mean tilt angles between the VOPcF 16 species and the substrate surface were 59 ± 5°and 30 ± 5°in the as-deposited and annealed films, respectively. For the sake of comparison, the structure of the thin films of vanadyl phthalocyanine (VOPc) was also studied. The mean tilt angle between the VOPc species and the substrate surface was found to be 77 ± 5°, in good agreement with existing experimental data (∼70°). All intense bands in the experimental IR and Raman spectra of VOPcF 16 and VOPc were assigned using DFT calculations (B3LYP) and the 15 N isotopic shifts in the vibrational spectra of VOPc.

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In the present work, we study and compare the structure and sensing properties of thin films of unsubstituted palladium phthalocyanine (PdPc) and hexadecafluorosubstituted palladium phthalocyanine (PdPcF 16 ). Thin films of PdPc and PdPcF 16 were obtained by the method of organic molecular beam deposition and their structure was studied using UV-visible spectroscopy, X-ray diffraction and atomic force microscopy techniques. The electrical sensor response of PdPc films toward ammonia and hydrogen was investigated and compared with that of PdPcF 16 films. The nature of interaction between the phthalocyanines films and some gaseous analyte molecules has been clarified using Quantum chemical (DFT) calculations.