The impact of replacement of nitrogen with phosphorus atom in the pyromellitic diimides on their photophysical and electrochemical properties.

Exploration of optoelectronic properties of novel phosphorus-embedded π-conjugated compounds would provide us with fundamental information about the design of hitherto unknown electroactive organic materials. Herein, detailed photophysical and electrochemical profiles of a series of benzene-cored diketophosphanyl compounds were investigated with steady- and time-resolved spectroscopic and spectroelectrochemical techniques. The comparative studies revealed the impact of phosphorus and nitrogen atoms on their triplet energies and on the behaviour of electrochemical processes to form radical species.