682
NEW BOOK8
The book does not possess the usual type of index. Besides the two bibliographies mentioned there is an “index of compounds,” which gives a complete tabulation of Raman work up to the present time. A further section called “numerical index” is a helpful aid for cross reference. The printing of the volume is done with care and the tables are neatly arranged, but the draftsmanship of the figures could be better. Scientific libraries, physicists, and chemists interested in the general field of molecular structure will need this compendium in their work. GEO. GLOCKLER.
Molecular Spectra and Molecule Structure. I . Diatomic Molecules. By G E R H A ~ D HZRZBERG.6 x 9 in.; xviii 592 pp. New York: Prentice-Hall, Inc., 1939. Price: 56.50. This book is the English translation of the German version; according to the author a number of additions have been made and in several places the text has been improved to cover more recent developments. The table containing the molecular constants for the normal state of diatomic molecules haa been revised to date (July, 1939). All workers in this country interested in band spectroscopy and the structure of molecules will welcome this volume aa presenting this intricate field of physics and chemistry in their own language, with a clarity of style and a forceful directness which cannot be surpassed. Similar books have been written, but the present volume portrays the subject with just the right balance between theory and experimental material t o make its perusal a distinct pleasure. Every chemist and physicist and all students interested in these branches of physical science will want t o own this work. Beginning students will have to read appropriate texts in wave mechanics in order to follow the presentation, for the author has wisely refrained from extraneous mathematical derivations which would only serve t o confuse the issues involved in any given discussion. After a short r6sum6 of the elementa of atomic structure in the first chapter, the remaining chapters (2 to 8) cover the following topics: Observed molecular spectra and their representation by empirical formulae; rotation and vibration of diatomic molecules, interpretation of infrared and Raman spectra; general discussion of electronic states and electronic transitions and their finer details; building-up principle, electron configurations, and valence ; continuous and diffuse molecular spectra, dissociation and predissociation and, finally, examples, results, and applications. The laat three chapters (6 to 8) will be of special interest to the chemist, for there is presented the modern picture of valency theory, at least in its beginnings, and several applications to other chemical topics, such as free radicals and photochemistry, are touched upon. However, the important function of this review is perhaps to stress the fact that the chemist must know some band spectroscopy if he would understand the modern approaoh to his own science. The book contains thirty-eight tables and one hundred and eighty-one illustrations. They really are works of art. The draftmanship is superb. The whole makeup of the volume is most excellent. The reviewer considers i t a privilege to have had the opportunity of reading this book. GEO. GLOCKLER.
+
