Deuterium isotope effect on the solid-state thermal isomerization of photo-coloured cis-keto species of N-salicylideneaniline

Deuterium isotope kinetic effect in the solid state was observed by using thermal fading reaction of photo-coloured species derived from Nsalicylideneaniline deuterohydroxyl derivative; thus, the existence of a cis-keto form in the photo-coloured Schiff base crystals was suggested experimentally along with 6-methyl-substitution effect on the stability of the photoproduct.