Surface photochemistry. The effects of coadsorbed molecules on pyrene luminescence and acenaphthylene dimerization on silica gel

Surface photochemistry: the effect of surface modification on the photophysics of naphthalene and pyrene adsorbed on silica gel

“…To verify this, a set of san~ples was prepared for which the silica gel was heated to 700°C in vacuum and, prior to naphthalene adsorption, a measured FIG. 4. Emission spectra of naphthalene: ( ( 2 ) silica gel heated to 700°C in vacuum for 4 h (Preparation ( c ) ) ; ( b ) silica gel heated at 700°C in vacuum for 4 h (Preparation ( c ) ) .…”

“…For methanol the values of A, and A, are both positive. In the former situation, therefore, kinetic excimer formation is dominant whereas ground state association predominates in the latter (4,30).…”

“…[3] and [4] For example, the percentage of the short decay component (7,) was calculated as 4, x 100.…”

“…The purpose of these investigations has been two-fold: to observe how the surface interactions may modify the behaviour of the excited molecules, and to use photochemistry as a tool to probe the substrate surface. Amongst the techniques employed that of fluorescent spectroscopy has so far been used most intensively both on silica gel (1)(2)(3)(4)(5), alumina (6)(7)(8)(9)(10)(11)(12)(13), and porous glass (14).…”

Synthesis, structure and properties of intercalation compounds containing perfluoroalkyl groups

“…9 formed in the film of intercalation compound. It has been reported that more than 95% and about 50% of acenaphthylene molecules in the singlet and triplet excited states, respectively provide synisomer [27,28]. As the result, syn/anti ratios of the dimers are more than 19 and about 1, when they are exclusively formed from the singlet and triplet excited states, respectively.…”