Spectroscopy Herzberg

A linear approximation of the potential is certainly too sweeping a simplification. In reality, Vr varies with the internuclear separation and usually rises considerably at short distances. This disturbs the perfect (mirror) reflection in such a way that the blue side of the spectrum (E > Ve) is amplified at the expense of the red side (E < 14).t For a general, nonlinear potential one should use Equations (6.3) and (6.4) instead of (6.6) for an accurate calculation of the spectrum. The reflection principle is well known in spectroscopy (Herzberg 1950 ch.VII Tellinghuisen 1987) the review article of Tellinghuisen (1985) provides a comprehensive list of references. For a semiclassical analysis of bound-free transition matrix elements see Child (1980, 1991 ch.5), for example. 

Far ultraviolet spectroscopy is nearly as old as ultraviolet spectroscopy Herzberg s volume III is the authoritative reference. For the more chemically minded spectro-scopist Robin s two volumes offer a framework based on chemical categories and nearly complete coverage. 

Lombardi, J.R., Birke, R.L., Lu, T., Xu, J. Charge-transfer theory of surface enhanced Raman spectroscopy Herzberg-Teller contributions. J. Chem. Phys. 84, 4174-4180 (1986)... 

The pre-eminent reference works in spectroscopy are the set of books by G Herzberg. 

Herzberg G 1971 The Spectra and Structures of Simple Free Radicals An Introduction to Molecular Spectroscopy (Ithaca, NY Cornell University Press)... 

The starting points for many conventions in spectroscopy are the paper by R. S. Mulliken in the Journal of Chemical Physics (23, 1997, 1955) and the books of G. Herzberg. Apart from straightforward recommendations of symbols for physical quantities, which are generally adhered to, there are rather more contentious recommendations. These include the labelling of cartesian axes in discussions of molecular symmetry and the numbering of vibrations in a polyatomic molecule, which are often, but not always, used. In such cases it is important that any author make it clear what convention is being used. 

Information about the structure of gas molecules haB been obtained by several methods. Spectroscopic studies in the infrared, visible, and ultraviolet regions have provided much information about the simplest molecules, especially diatomic molecules, and a few polyatomic molecules. Microwave spectroscopy and molecular-beam studies have yielded very accurate interatomic distances and other structural information about many molecules, including some of moderate complexity. Molecular properties determined by spectroscopic methods are given in the two books by G. Herzberg, Spectra of Diatomic Molecules, 1950. and Infrared and Raman Spectra, 1945, Van Nostrand Co., New York. The information obtained about molecules by microwave spectroscopy is summarised by C. H. Townes and A. L. Schawlow in their book Microwave Spectroscopy of Gases, McGraw-Hill Book Co., New York, 1955. 

B-45MI22600 G. Herzberg infrared and Raman Spectroscopy , Van Nostrand Reinhold,... 

In spite of many studies the complete analysis of the ultraviolet absorption spectrum has not been successful [Herzberg (16), p. 511]. The spectroscopy and photochemistry of S02 may be conveniently discussed for four... 

As a purely pragmatic device we have chosen operational criteria as a rather loose basis for organization. Since we are not attempting a literature survey, references are limited, but include the classics by Herzberg(l,2) Noyes and Leighton (3), and Pringsheim (4), key articles and reviews by Mulliken (5,6), Platt (7,8), and Kasha (9) and three recent books on various aspects of spectroscopy in which nomenclature is discussed and terms are defined (10-12). We also have utilized a manuscript in preparation by Calvert and Pitts (13). ... 

Herzberg, G. Molecular spectroscopy and molecular structure. II. Infrared and raman spectra of polyatomic molecules. New York, Cincinnati, Toronto, London, and Melbourne Van Nostrand Reinhold Company 1945... 

The principles of electronic spectroscopy have been discussed by Herzberg (1950) for diatomic molecules, and in a classic review by Sponer and Teller (1941) for the more general case of polyatomic structures. Recent developments are described in articles appearing regularly in the Annual Reviews of Physical Chemistry. Triatomic molecules and radicals have been intensively studied, the latter by the powerful method of flash photolysis (Herzberg, 1959). As triatomic structures have been comprehensively reviewed recently (Ramsay, 1962) we include in this article only those triatomic systems that are of particular interest in organic chemistry. Otherwise attention will be directed to molecules of four or more atoms, including all known representatives of the important chromophores. 

Photodissociation combines aspects of both molecular spectroscopy and molecular scattering. The spectroscopist is essentially interested in the first step of Equation (1.1), i.e., the absorption spectrum. In the past six decades or so methods of ever increasing sophistication have been developed in order to infer molecular geometries from structures in the absorption or emission spectrum (Herzberg 1967), whereas the fate of the fragments, i.e., the final state distribution is of less relevance in spectroscopy. The decay of the excited complex is considered only inasfar as the widths of the individual absorption lines reflect the finite lifetime in the excited state and therefore the decay rate of the excited molecule. 

In 1950, microwave and molecular beam methods were just beginning to be developed, and they are mentioned briefly by Herzberg in his book. Microwave spectroscopy was given a boost by war-time research on radar, with the development of suitable radiation sources and transmission components an early review of the... 

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