Some features of the molecular assembly of copper porphyrazines

Floating layers and Langmuir–Blodgett (LB) films of copper porphyrazine (CuPaz) and its tetra-tert-butyl-substituted homologue (CuPazʹ) are studied. Contrary to phthalocyanines, the monolayer phase in the porphyrazine layers is metastable and transforms directly into the tetralayer one under moderate compression. In diffraction patterns and electronic spectra of the LB films, supramolecular peaks indicating collectivizing of the molecular electron density in direction perpendicular to the main axis of the macrocycle are found. The data obtained indicate the prismatic 3-D supermolecule to be the simplest structural unit of the porphyrazine assembly.