A spectrophotometric study of impact of solvent, substituent and cross-conjugation in some 4-aminoantipyrine based Schiff bases

Cross-conjugation controls the stabilities and photophysical properties of heteroazoarene photoswitches

“…Cross-conjugated molecules have incomplete π-delocalization, which has been shown to impact photophysical properties by increasing molecular band gaps and lowering λ max absorption. [52][53][54][55] Cross-conjugation has also been found to affect the reversibility and activation free energy barriers of Diels-Alder and thiol addition reactions. [56][57][58] The delocalization effect in 1-E and 3-E leads to higher-lying HOMOs and lower-lying LUMOs relative to 2-E and 4-E, leading to increased HOMO-LUMO gaps.…”