Photochemistry 7

The breadth of scientific and technological interests in the general topic of photochemistry is truly enormous and includes, for example, such diverse areas as microelectronics, atmospheric chemistry, organic synthesis, non-conventional photoimaging, photosynthesis, solar energy conversion, polymer technologies, and spectroscopy. This Specialist Periodical Report on Photochemistry aims to provide an annual review of photo-induced processes that have relevance to the above wide-ranging academic and commercial disciplines, and interests in chemistry, physics, biology and technology. In order to provide easy access to this vast and varied literature, each volume of Photochemistry comprises sections concerned with photophysical processes in condensed phases, organic aspects which are sub-divided by chromophore type, polymer photochemistry, and photochemical aspects of solar energy conversion. Volume 34 covers literature published from July 2001 to June 2002. Specialist Periodical Reports provide systematic and detailed review coverage in major areas of chemical research. Compiled by teams of leading authorities in the relevant subject areas, the series creates a unique service for the active research chemist, with regular, in-depth accounts of progress in particular fields of chemistry. Subject coverage within different volumes of a given title is similar and publication is on an annual or biennial basis.

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.

The breadth of scientific and technological interests in the general topic of photochemistry is truly enormous and includes, for example, such diverse areas as microelectronics, atmospheric chemistry, organic synthesis, non-conventional photoimaging, photosynthesis, solar energy conversion, polymer technologies, and spectroscopy. This Specialist Periodical Report on Photochemistry aims to provide an annual review of photo-induced processes that have relevance to the above wide-ranging academic and commercial disciplines, and interests in chemistry, physics, biology and technology. In order to provide easy access to this vast and varied literature, each volume of Photochemistry comprises sections concerned with photophysical processes in condensed phases, organic aspects which are sub-divided by chromophore type, polymer photochemistry, and photochemical aspects of solar energy conversion. Volume 34 covers literature published from July 2001 to June 2002. Specialist Periodical Reports provide systematic and detailed review coverage in major areas of chemical research. Compiled by teams of leading authorities in the relevant subject areas, the series creates a unique service for the active research chemist, with regular, in-depth accounts of progress in particular fields of chemistry. Subject coverage within different volumes of a given title is similar and publication is on an annual or biennial basis.

Spacecraft study of the Solar system is one of humanity's most outstanding achievements. Thanks to this study, our present knowledge of properties of and conditions on the planets exceeds many-fold that of 20 years ago: planets have been rediscovered. This is especially the case for planetary atmospheres, whose properties were for the most part either not at all or only erroneously known. Much research has been invested in the study of the atmospheres of Mars and Venus, and their chemical composition and photochemistry are basic problems in these studies. In the present publication I have tried to summarize all findings in this field. The English version of the book includes new data in the field from the last 3 years since the book was published in Russian. I wish to thank U. von Zahn, who initiated my talks with Springer-Verlag and acted as technical editor. December 2, 1985 V. A. KRASNOPOLSKY Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 Chemical Composition and Structure of the Martian Atmosphere 4 1. 1 Carbon Dioxide and Atmospheric Pressure . . . . . . . . . . . . . . . . . . . 4 1. 2 CO and O Mixing Ratios . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2 1. 3 Ozone. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1. 4 Water Vapor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 1. 5 Composition of the Upper Atmosphere as Determined from Airglow Spectroscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 1. 6 Mass Spectrometric Measurements of the Atmospheric Composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 1. 7 Ionospheric Composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 1. 8 Temperature Profile of the Lower Atmosphere. . . . . . . . . . . . . . . . 36 1. 9 Temperature of the Upper Atmosphere . . . . . . . . . . . . . . . . . . . . . . 40 1. 10 Eddy Diffusion Coefficient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 2 Photochemistry of the Martian Atmosphere . . . . . . . . . . . . . . . . . .

Revised and updated in 2000, Basic Physical Chemistry for the Atmospheric Sciences provides a clear, concise grounding in the basic chemical principles required for studies of atmospheres, oceans, and earth and planetary systems. Undergraduate and graduate students with little formal training in chemistry can work through the chapters and the numerous exercises within this book before accessing the standard texts in the atmospheric chemistry, geochemistry, and the environmental sciences. The book covers the fundamental concepts of chemical equilibria, chemical thermodynamics, chemical kinetics, solution chemistry, acid and base chemistry, oxidation-reduction reactions, and photochemistry. In a companion volume entitled Introduction to Atmospheric Chemistry (2000, Cambridge University Press) Peter Hobbs provides an introduction to atmospheric chemistry itself, including its applications to air pollution, acid rain, the ozone hole, and climate change. Together these two books provide an ideal introduction to atmospheric chemistry for a variety of disciplines.

Photochemistry and Photophysics is a multi-volume set that presents a critical review of new developments that have occurred in the inorganic, organic, atmospheric, environmental, material, bio-and polymer fields of photochemistry and photophysics over the last decade. Specific topics covered in Volume III include photochemical processes at semiconductors, photoluminescence probes of porous solids, photoluminescence probes of polymer structures, and photomodification of cell membranes. Topics covered in Volume IV include magnetic fields in photochemistry, heterogenous photocatalysis by semiconductor powders, hydrophobic and hydrophyllic effects on photochemical and photophysical processes, and photoinitiators for free radical polymerization. The book provides essential information for students and researchers in photochemistry and photophysics.

In the past fifteen years organic photochemistry has undergone a greater change and has stimulated more interest than probably any other area of organic chemistry. What has resulted is a population explosion, that is, an ever-increasing number of organic chemists are publishing important and exciting research papers in this area. Professor Bryce-Smith in the introduc tion to a recent volume of the Specialist Periodical Report (Photochemistry, Volume 6), which reviews the photochemical literature in yearly intervals, states that "the flood of photochemical literature is showing some signs of abatement from the high levels of two or three years ago .... " However, Volume 6 of that periodical contains 764 pages of excellent but very concise reviews. We expect the development of the mechanistic aspects of organic photo chemistry to continue at the present pace as new methods are developed to probe in increasing detail and shorter time scales the photochemical dynamics of both old and new photoreactions. Since photochemistry is no longer the sole domain of the specialist, it is relatively safe to predict a dramatic increase in the near future of the synthetic and industrial uses of organic photo chemistry .

Photochemistry is an important facet in the study of the origin of life and prebiotic chemistry. Solar photons are the unique source of the large amounts of energy likely required to initiate the organisation of matter to produce biological life. The Miller–Urey experiment simulated the conditions thought to be present on the early earth and supported the hypothesis that under such conditions complex organic compounds could be synthesised from simpler inorganic precursors. The experiment inspired many others, including the production of various alcohols, aldehydes and organic acids through UV-photolysis of water vapour with carbon monoxide. This book covers the photochemical aspects of the study of prebiotic and origin of life chemistry an ideal companion for postgraduates and researchers in prebiotic chemistry, photochemistry, photobiology, chemical biology and astrochemistry.