Photochemistry — 7 is a collection of plenary lectures presented at the Seventh Symposium on Photochemistry held in Leuven, Belgium, on July 24-28, 1978. Contributors explore a wide range of topics relating to photochemistry, including the chemistry of exciplexes and the photo-oxidation of polymers. Excited state electron-transfer reactions of transition metal complexes are also discussed, along with the photochemistry of diazocompounds and azides in argon. This volume is comprised of 12 chapters and begins with a review of the role of exciplex intermediates in photocycloadditions involving polyenes and excited anthracenes. The reader is then introduced to the use of photochemical conversion of one molecule into another as an approach to the synthesis of natural products. The following chapters focus on the use of the Linear Combination of Fragment Configurations approach to generate qualitative potential energy surfaces; reciprocal interactions of polymers with excited solutes or polymer-bound chromophores; photochemistry of some three-membered heterocycles; cis-trans photoisomerization of 4-nitrostilbenes; and electron transfer in monolayer assemblies. This monograph will be of value to chemists.