Spectral and photochromic properties of two long-chain spiropyranindoline monolayers at the air–solid interface

Abstract

Some long-chain spiropyranindolines have been studied at the air–water and the air–solid interfaces. We have measured the surface pressure–area isotherms of these compounds and two of them are characterized by a solid film. We have also investigated the spectroscopic properties (uv–visible) of these spiropyranindolines in monolayer and in solution. The deposition of monolayers on quartz slides allowed the study of the photochromic properties of these compounds at the air–solid interface. The 3′,3′-dimethyl-1′-hexadecyl-6-nitrospiro(2H-1-benzopyran-2,2′-indoline), irradiated at 253.7 nm, showed the appearance of a new absorption band at 570 nm which varied in intensity when the number of monolayers and the time of irradiation were changed.