Atomic and Molecular Photoabsorption: Partial Cross Sections is a companion work to Joseph Berkowitz's earlier work, Atomic and Molecular Photoabsorption: Absolute Total Cross Sections, published with Academic Press in 2002. In this work Joseph Berkowitz selected the "best" absolute partial cross sections for the same species as included in the companion work. A contrast, however, is that photoabsorption measurements, being of order I/Io, do not require the most intense light sources, whereas acquiring data on the products of light interactions with gaseous matter (ions, electrons, various coincidence measurements) has benefited significantly with the arrival of second- and third-generation synchrotrons. The newer devices have also extended the energy range of the light sources to include the K-shells of the species discussed here. The newer light sources encouraged experimentalists to develop improved instrumentation. Thus, the determination of partial cross sections continues to be an active field, with more recent results in some cases superseding earlier ones. Where the accuracy of the absolute partial cross sections is deemed sufficient (less than five percent), numerical tables are included in this new work. In other cases, the available data are presented graphically. - Includes data on atoms, diatomic molecules, triatomic molecules, and polyatomic molecules - Written by world-leading pioneer in the field of photoionization mass spectrometry - Very clear presentation of the useful, quantitative information in both tables and graphs

The procedure for estimation of heats of formation of compounds is illustrated by discussion of compounds of several of the elements of the actinide series. The procedure is particularly suited for lanthanide and actinide elements because of the similarity of the ionic radii and types of bonding.

Comprises 20 contributions which grew from the August 1996 symposium. Representative paper topics include estimating phase- change enthalpies and entropies, electrostatic-covalent model parameters for molecular modeling, complete basis-set thermochemistry and kinetics, modeling free energies of solvation and transfer, use of density functional methods to compute heats of reaction, and a density functional study of periodic trends in bond energies. Together the contributions describe all the major methods used for estimating or predicting molecular thermochemistry. Appends information on software and databases for thermochemistry, essential statistical thermodynamics, and worked examples. Annotation copyrighted by Book News, Inc., Portland, OR

In thermochemical calculations, it is frequently necessary to estimate the standard heat of formation of compounds for which experimental data are unavailable. Although there are several methods that may be used, none is completely reliable or general. It was the purpose of this research to develop a more reliable and/or more general method of estimation. To do this several modifications were made to the work done by Linus Pauling in developing a scale of electronegativity. The result is a simple equation. - DELTA H/sub f/ = nu /sub AB/ (X/sub B/ - X/sub A/)/sup 2/ + nu /sub A/ Y/sub A/ + nu /sub B/ Y/sub B/, where nu /sub AB/is the apparent number of single bonds, nu /sub A/ is the number of atoms A in the mole, and nu /sub B/ is the number of atoms B in the mole, with a set of parameters x and Y. Each valence state of each element may be assigned a value x and a value Y. Where these parameters have not been determined, they may be calculated for any cation when experimental heats of formation of two compounds of the cation are known. The equation applies primarily to metallic halides, although it may also be used (with reservation) for pther anions, including carbonates, sulfates, and similar radicals. It is not restricted to binary compounds. The average deviation obtained for a set of the halides of twenty-two metals was 0.93 kcal/mole. An error of less than 10 kcal/mole may generally be expected in estimating an unknown using only two experimental data. (auth).

Chemistry 2e is designed to meet the scope and sequence requirements of the two-semester general chemistry course. The textbook provides an important opportunity for students to learn the core concepts of chemistry and understand how those concepts apply to their lives and the world around them. The book also includes a number of innovative features, including interactive exercises and real-world applications, designed to enhance student learning. The second edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Substantial improvements have been made in the figures, illustrations, and example exercises that support the text narrative. Changes made in Chemistry 2e are described in the preface to help instructors transition to the second edition.