Photochemical E(trans)―Z(cis)―E Isomerization of an Amphiphilic Cholest-5-en-3β-yl(E)-9-anthraceneprop-2-enoate on Solid Substrate

Surface morphology and photochemical isomerization properties of monolayers of anthrancene acrylic acid derivative with cholesterol (a new class of bistable compound), cholest-5-en-3β-yl(E)-9-anthraceneprop-2-enoate (CAE), transferred onto quartz substrates were studied. The spectroscopic and photochromic behavior of CAE on solid substrates and in solution are compared keeping in mind the possible application of CAE in constructing molecular electronic devices. Monolayers of the trans(E)-isomer of CAE transferred from the air–water interface onto quartz plates show regular distribution of “holes” in the film, whereas similar monolayers of the cis(Z)-isomer of CAE (∼96%) show very smooth surfaces, free from any definite structures. The surface pressure–area (π–A) isotherms of both monolayers at the air–water interface are found to be irreversible, indicating formation of 2D/3D aggregates for both isomers. The surface potential–area (ΔV–A) isotherms of the two isomers predict the orientation of their molecu...