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Excited states in organic chemistry and biochemistry
401
range of the subject,-from reviews giving historical perspective, through analyses of the theories of magnetic polarisation, to accounts of recent applications. The weight of the papers also covers the full range of possibilities: some are descriptive and could profitably be read on a train journey, while at the other end of the spectrum others have the full heaviness of advanced and sophisticated theory, and really require pencil and paper, and peace and quiet, if they are to be studied seriously. I was pleased to find quite a useful amount of experimental information, for I wonder if experimental aspects sometimes tend to be under-represented in reports these days and this always strikes me as a little odd: it does not always seem to be satisfactory for someone to be able to interpret (or claim to be able to interpret) experimental results if he does not know how to obtain them himself. I regard this as a timely and useful book. It should be available in all magnetic resonance laboratories.
N. M. A.
St&es in Organic Chemistry and Biochemistry, Proceedings of the Tenth Jerusalem Symposium on Quantum Chemistry and Biochemistry, edited by B. Pullman and N. Goldblum, D. Reidel, Dordrecht and Boston, 1977, pp. xiii + 448, price US $39.50.
Excited
The 37 papers presented at this conference are very wide ranging with, at the one extreme, articles on theoretical calculations on unimolecular decays of excited states of CH,+ and H,G+ (Lorquet et al.), on solvent effects (Hall and Miller), on excited states of saturated molecules (Gordon and Caldwell), and on non-empirical calculations of excited states by the method of improved virtual orbitals (Janoschek), while at the other extreme several papers report experiments on excited states of nucleic acids, for example those by Vigny and ZWlini, and by Montenay-Garestier, on emission and energy transfer at 300 K and 77 K, respectively, and on photochemical cross-linking in protein-nucleic acid complexes by Sperling and Havron. Mechanisms for radiation damage in DNA and for fluorescence quenching in protein-nucleic acid complexes are discussed by Sevilla and Helene, respectively, while Rahn discusses the influence of Hg2+ on the photochemistry of DNA, and Hiittermann deals with excitation and ionisation of 5 halo-uracils. Circular dichroism is featured in several papers, including those by Snatzke and Hajos on chiral pyrazines, and by Maestre et al. on the T4 gene product 3.2 protein-DNA interaction_ Both Bush and Pysh report experiments on far-ultraviolet circular dichroism of oligosaccharides and polypeptides, while theoretical treatments of chiroptic properties of small peptides and proteins
402
are given by Hooker and Goux and by Iseli et al. A variety of other techniques, such as time-resolved fluorescence spectra, mono-photon sampling techniques, laser flash photolysis, etc., are featured in the following: “intramolecular excited states interactions in 1,3 di (Z-anthryl) propane” (de Schrywer et al.); “influence of 3-substitution on excited-state properties of indole” (Laustiat et al.); “excited states of aromatic amino acids and peptides” (Hayon); and “interaction of the flavin ring system and amino acids” (McCormick). McGlynn et al. describes the photoelectron spectroscopy of carbonyls and biological considerations. However, with the average length of each paper being only 11 pages, not much-z experimental detail or extensive discussion is possible. Three papers deal with aspects of vision and photoreceptors, viz., “photoreceptors and photoprocesses in the living cell” (Wolken), “electron-electron interaction and resonant optical spectral shifts in photoreceptor molecules” (Dunne), and “the sudden polarisation effect” (Salem). Carcinogenic activity of aromatic hydrocarbons is discussed in articles by Politzer and Daiker, and by Selinger and Harmman. Other papers discuss the photochemistry of vicinal polyketones (Rubin), of C-nitroso compounds in the presence and absence of O2 (de Boer et al.), of acidified solutions of 4-methylumbelliferone (Kindt and Lippert), and decay paths of excited conjugated dienes (Boue et al.). In addition to the wide variety of subjects already listed, Wang reports on a “hot” ground state intermediate in the photohydration of pyrimidines, and Michl et al. discuss higher excited states and vibrationally-hot excited states in organic photochemistry. Other titles include “fluorescence from upper excited singlet states” (Wild), “electronic structure and photophysical properties of planar conjugated hydrocarbons with a 4rz-membered ring” (Wirz), “evidence and reactivity of a twisted form of medium size cycle-alkene rings presenting a double band past orthogonality” (Joussot-Dubien et al.), and “wavelength dependence of $F and $ (e> ) of some aromatic amines in aqueous solution” (Kohler et al.)_ Although the subject matter is very diverse a wealth of information is given even if it is, because of the shortness of the papers, in abridged form. F. W.
Introduction to Elementary Molecular Orbital Theory and to Semiempirical Methods, by Georges Henry Wagniere, Vol. 1 of Lecture Notes in Chemistry,
series editors G. Berthier, M. J. S. Dewar, II. Fischer, K. Fukui, H. Hartmann, H. H. Jaffe, J. Jortner, W. Kutzelnigg, K. Ruedenbzrg, E. Scrocco and W. Zeil, Springer-Verlag, Eerlin, Heidelberg and New York, 1976, pp. 109, DM 14.80. Lectures given in 1974 at the University of Zurich and at the Seminario Latinoamericano di Quimica Cuantica in Mexico, form the basis of these notes, which summa&e and introduce elementary molecular orbital theory
range of the subject,-from reviews giving historical perspective, through analyses of the theories of magnetic polarisation, to accounts of recent applications. The weight of the papers also covers the full range of possibilities: some are descriptive and could profitably be read on a train journey, while at the other end of the spectrum others have the full heaviness of advanced and sophisticated theory, and really require pencil and paper, and peace and quiet, if they are to be studied seriously. I was pleased to find quite a useful amount of experimental information, for I wonder if experimental aspects sometimes tend to be under-represented in reports these days and this always strikes me as a little odd: it does not always seem to be satisfactory for someone to be able to interpret (or claim to be able to interpret) experimental results if he does not know how to obtain them himself. I regard this as a timely and useful book. It should be available in all magnetic resonance laboratories.
N. M. A.
St&es in Organic Chemistry and Biochemistry, Proceedings of the Tenth Jerusalem Symposium on Quantum Chemistry and Biochemistry, edited by B. Pullman and N. Goldblum, D. Reidel, Dordrecht and Boston, 1977, pp. xiii + 448, price US $39.50.
Excited
The 37 papers presented at this conference are very wide ranging with, at the one extreme, articles on theoretical calculations on unimolecular decays of excited states of CH,+ and H,G+ (Lorquet et al.), on solvent effects (Hall and Miller), on excited states of saturated molecules (Gordon and Caldwell), and on non-empirical calculations of excited states by the method of improved virtual orbitals (Janoschek), while at the other extreme several papers report experiments on excited states of nucleic acids, for example those by Vigny and ZWlini, and by Montenay-Garestier, on emission and energy transfer at 300 K and 77 K, respectively, and on photochemical cross-linking in protein-nucleic acid complexes by Sperling and Havron. Mechanisms for radiation damage in DNA and for fluorescence quenching in protein-nucleic acid complexes are discussed by Sevilla and Helene, respectively, while Rahn discusses the influence of Hg2+ on the photochemistry of DNA, and Hiittermann deals with excitation and ionisation of 5 halo-uracils. Circular dichroism is featured in several papers, including those by Snatzke and Hajos on chiral pyrazines, and by Maestre et al. on the T4 gene product 3.2 protein-DNA interaction_ Both Bush and Pysh report experiments on far-ultraviolet circular dichroism of oligosaccharides and polypeptides, while theoretical treatments of chiroptic properties of small peptides and proteins
402
are given by Hooker and Goux and by Iseli et al. A variety of other techniques, such as time-resolved fluorescence spectra, mono-photon sampling techniques, laser flash photolysis, etc., are featured in the following: “intramolecular excited states interactions in 1,3 di (Z-anthryl) propane” (de Schrywer et al.); “influence of 3-substitution on excited-state properties of indole” (Laustiat et al.); “excited states of aromatic amino acids and peptides” (Hayon); and “interaction of the flavin ring system and amino acids” (McCormick). McGlynn et al. describes the photoelectron spectroscopy of carbonyls and biological considerations. However, with the average length of each paper being only 11 pages, not much-z experimental detail or extensive discussion is possible. Three papers deal with aspects of vision and photoreceptors, viz., “photoreceptors and photoprocesses in the living cell” (Wolken), “electron-electron interaction and resonant optical spectral shifts in photoreceptor molecules” (Dunne), and “the sudden polarisation effect” (Salem). Carcinogenic activity of aromatic hydrocarbons is discussed in articles by Politzer and Daiker, and by Selinger and Harmman. Other papers discuss the photochemistry of vicinal polyketones (Rubin), of C-nitroso compounds in the presence and absence of O2 (de Boer et al.), of acidified solutions of 4-methylumbelliferone (Kindt and Lippert), and decay paths of excited conjugated dienes (Boue et al.). In addition to the wide variety of subjects already listed, Wang reports on a “hot” ground state intermediate in the photohydration of pyrimidines, and Michl et al. discuss higher excited states and vibrationally-hot excited states in organic photochemistry. Other titles include “fluorescence from upper excited singlet states” (Wild), “electronic structure and photophysical properties of planar conjugated hydrocarbons with a 4rz-membered ring” (Wirz), “evidence and reactivity of a twisted form of medium size cycle-alkene rings presenting a double band past orthogonality” (Joussot-Dubien et al.), and “wavelength dependence of $F and $ (e> ) of some aromatic amines in aqueous solution” (Kohler et al.)_ Although the subject matter is very diverse a wealth of information is given even if it is, because of the shortness of the papers, in abridged form. F. W.
Introduction to Elementary Molecular Orbital Theory and to Semiempirical Methods, by Georges Henry Wagniere, Vol. 1 of Lecture Notes in Chemistry,
series editors G. Berthier, M. J. S. Dewar, II. Fischer, K. Fukui, H. Hartmann, H. H. Jaffe, J. Jortner, W. Kutzelnigg, K. Ruedenbzrg, E. Scrocco and W. Zeil, Springer-Verlag, Eerlin, Heidelberg and New York, 1976, pp. 109, DM 14.80. Lectures given in 1974 at the University of Zurich and at the Seminario Latinoamericano di Quimica Cuantica in Mexico, form the basis of these notes, which summa&e and introduce elementary molecular orbital theory