Photochemistry on Surfaces

Photochemistry on surfaces, solids, inclusion compounds and other organized media continue to be the subject of considerable attention (10-15). Zeolites offer a new possibility in the study of photoprocesses in ordered media, and the study of guest-host... 

Vinodgopal, K. Kamat, P. V. Photochemistry on surfaces. Photodegradation of 1,3-diphenylisobenzofuran over metal oxide particles, J. Phys. Chem. 1992, 96, 5053. 

The EH calculations agree with the CNDO results if a planar nondefect geometry is used. When the model containing defects serves as the lattice, electron-capture processes are favored at the expense of Ag+ capture at the Ag center, as shown in Table XIII. This leads to the alternative pathway shown in Fig. 24, and would explain a dependence of photochemistry on surface-defect structure. 

Wilkinson, F., Leicester, P.A., Ferreira, L.F.V., and Freires, V.M.M.R. (1991) Photochemistry on surfaces triplet-triplet energy transfer on microcrystalline cellulose studied by diffuse reflectance transient absorption and emission spectroscopy, Photochem. Photobiol., 54, 599-608. 

L.F. Vieira Ferreira, J.C. Netto-Ferreira, I.V. Kmelinskii, A.R. Garcia, and S.M.B Costa, "Photochemistry on surfaces matrix isolation mechanisms for study of interactions of ben-zophenone adsorbed on microcrystalline cellulose investigated by diffuse reflectance and luminescence techniques", Langmuir, Vol. 11, pp. 231-236,1995. 

The fluorescence quantum yield of the polymers in toluene solution is measured by comparison to that of 9-anthracene carboxylic acid Kamat, P. V., and Ford, W. F., Photochemistry on surfaces triplet-triplet energy transfer on colloidal TiO particles, Chem. Phys. Lett, 135, 421 (1987). 

September 4-8,1988 edited by H.G. Karge and J. Weitkamp Volume 47 Photochemistry on Solid Surfaces edited by M. Anpo andT. Matsuura... 

Kamat PV (1993) Photochemistry on nonreactive (semiconductor) surfaces. Chem Rev 93 267-300... 

M. Anpo and T. Matsuura (eds.), Photochemistry on Solid Surfaces, Eisevier, Amsterdam (1989). 

My years of cooperation with Moshe at the Weizmann Institute preceded his brilliant work on coherent control. However, the qualities that led him to his highlight work were all there the sharpness of his thinking, his grasp of formal theory, and the insights into experimental implications. My choice of photochemistry as the topic of my contribution was influenced by his long-term interest in photodissociation and the fact that we had cooperated, among other topics, on photochemistry at surfaces. 

While the importance of the breakdown of the BOA in thermal chemistry is still controversial, the time-reversed process of creating chemistry from hot electrons is well established. Because experiments are generally performed under conditions where there is no adiabatic chemistry, hot electron induced chemistry is easily identified and studied, even when the cross-section for the chemistry is very small. Typical scenarios involve photochemistry, femtochemistry and single molecule chemistry on surfaces. A few well-studied examples are discussed briefly in Section 4.8. Because a detailed discussion of these active fields would take this chapter far from its original purpose, they are only treated briefly to illustrate the relationship to other aspects of bond making/breaking at surfaces. 

The immobilization of photoactive species into the silica-surfactant mesostructured materials is worth investigating toward future photofunctional materials. Photochemistry on solid surfaces is a growing new field which yields a wide variety of useful application such as sensitive optical media, reaction paths for controlled photochemical reactions, molecular devices for optics, etc. [17] Along this line, the incorporation of organic dyes into silica-surfactant mesostructured materials [17-20] as well as nanoporous silica films[3] have been reported so far. 

Studies of inorganic photochemistry in unusual environments has attracted considerable attention. Photochemical studies conducted in organized assemblies such as micelles, microemulsions and vesicles,217 on surfaces such as porous Vycor glass,218 in a lamellar solid,219 and in the gas phase have been reported.220... 

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