Bibliography

A. N. TERENIN, Introduction to Spectroscopy, published by KUBUCH, Leningrad, 1933, 312 pp.

The purpose of the book under review is to give a brief survey of the present state of the question of the optical spectra of atoms and molecules. In a single small volume it would be impossible to give an exhaustive exposition of the entire subject; therefore the author has confined himself to presenting selected chapters from this important field of modern physics, striving to cast this exposition in a form accessible to beginners. Terenin’s book is not an experimental book: it contains only a very small number of indications concerning experimental technique (a description of several experimental arrangements for observing optical excitation of spectra and excitation connected with collisions—this is almost all that relates in Terenin’s book to the specifically experimental side of the matter). Therefore the book should be regarded as a theoretical book intended for beginners, although the author himself makes no such claim: “…in this book,” he says in his preface, “the basic information is set forth concerning the structure of atoms and molecules and the processes occurring in them, as obtained by the analysis of spectra… Such details and auxiliary calculations have deliberately been avoided, the cumbersome nature of which would have disrupted the main line of exposition. The theory of the question and a rigorous justification of the propositions advanced may be found in the literary sources indicated at the end of each chapter.”

The first two parts of the book, which occupy half of its text, contain a survey of those features of the structure of atoms that can be investigated by analyzing only the frequencies of spectral lines (but not their intensities, etc.). The exposition is historical throughout: after describing certain basic concepts of classical electrodynamics necessary for understanding the book, the author gives an account of Bohr’s theory of hydrogen-like atoms (including the correspondence principle and the selection rule). The following chapters contain a survey of the serial structure of the spectra of alkali metals, X-ray series, and the multiplet structure of terms. Also described are the vector model of the atom, the connection of multiplet structure with chemical valence, the Pauli principle (in its quantum-mechanical form), and the periodic system of the elements. Fifteen pages are devoted to a concise exposition of wave mechanics, followed by an elementary survey of the Zeeman and Stark effects.

The third part of the book is devoted to the excitation of spectra: first excitation by transfer of kinetic energy is described, and then optical excitation (optical resonance and fluorescence). This is followed by a very elementary chapter on the intensity and natural width of spectral lines. The question of the influence of collisions on the width and intensity of lines is also analyzed (including a brief survey of the phenomena of quenching of luminescence by collisions and of sensitized fluorescence).

The fourth part is a survey of molecular spectra. This survey includes almost exclusively diatomic molecules. Electronic, vibrational, and rotational transitions and all possible connections between them are considered, including the Raman effect discovered by Raman, Landsberg, and

Bibliography

Mandelstam combination scattering. The last chapter contains certain questions closely connected with chemistry (molecular energy, the Franck–Condon principle, predissociation).

The greatest shortcoming of the book under review is the absence of a principled approach in the selection of the material presented. Thus, for example, one cannot indicate any reasonable grounds for why a book such as this includes nothing concerning hyperfine structure, why X-ray spectra are touched upon only in passing, and so on. But the book also has important merits: clarity and accessibility of exposition, thanks to which it should be warmly recommended to every student for a first acquaintance with this very interesting, though arbitrarily selected and limited, material.

M. Bronstein