Time‐resolved resonance Raman study of photochromic 4‐(2′, 4′‐dinitrobenzyl)pyridine

摘要

AbstractTwo transient species involved in the photochromism of 4‐(2′, 4′‐dinitrobenzyl)pyridine have been detected by time‐resolved resonance Raman spectroscopy. Comparison of the spectra of the shorter and longer lived transient species with those of the anion and theN‐CH3derivative, respectively, revealed that the shorter lived species is identical with the anion and the longer lived species is the NH quinoid tautomer. It is shown that the photochromism of this compound can be interpreted in terms of the involvement of the anion as the intermediate to the NH quinoid which is the photo‐activated transient blue substance