Spectroscopic identification of conjugated polymeric phthalocyanines

TL;DR

This paper clarifies the spectral signatures of conjugated polymeric phthalocyanines, distinguishing well-polymerized forms from monomers, and emphasizes the importance of correct spectral assignment for accurate identification.

Contribution

It demonstrates that previous spectral data often misidentified early reaction intermediates as fully polymerized PPCs, providing corrected spectral signatures supported by experimental and DFT data.

Findings

Spectral data often misassigned to fully polymerized PPCs.

Octacyano phthalocyanine (OCP) is an early reaction intermediate.

Correct spectral signatures distinguish monomeric and polymerized PCs.

Abstract

Since the discovery of polyphthalocyanines (PPCs) in late 1950s, numerous attempts have been made to synthesize this 2D polymer by different approaches. Interestingly, the reported IR, Raman and UV-vis spectra of PPCs show drastic variation depending on the synthesis conditions. In this work, we show that the spectral data obtained in some works should be assigned not to the target polymer, but rather to octacyano phthalocyanine (OCP), which is an early step of the reaction. We discuss the spectral signatures of the well-polymerized and monomeric PCs based on reliable experimental data and support the spectral assignments with DFT calculations.