Oriented structures of lead phthalocyanine thin films: IR studies and normal coordinate calculations of the non-planar porphin ring system

摘要: Abstract Mid-IR spectra of lead phthalocyanine (PbPc) thin films show a pronounced dependence on the sublimation rate and substrate temperature during film preparation under ultrahigh vacuum conditions. Below 400 K PbPc can be prepared in quasi-monoclinic form, whereas high amounts quasi-triclinic form are produced at higher temperatures. These structures were identified from an analysis spectral changes between two modifications. For this purpose, simplified normal coordinate model calculations performed for porphin ring system with C 4v 2v symmetry respectively.