Abstract

The lattice vibration spectrum of a solid has recently been characterized by one single frequency, which is defined as the frequency of the center of gravity of the spectrum, called “centro-frequency”. Here the experimental determination of this frequency is shown in detail for a number of solids the vibrational spectra of which became available recently. Emphasis is given to spectral data at various temperatures, from 4°K to about 1000°K, and at the various major crystallographic directions. The “centro-frequencies” at room temperature and higher temperatures show almost no change; whereas, at low temperature, the “centro-frequencies” consistently show a very definite increase. The result reveals a definite increase in binding energy with temperature decrease. A considerably higher resolution, particularly in the broad band areas, was obtained with spectra at very low temperatures.

© 1964 Optical Society of America

Characteristic Spectra of Energy Absorption for Dielectric Solids

J. N. Plendl
Appl. Opt. 9(12) 2768-2786 (1970)

Characteristic Frequencies from Infrared and Elastic Data

Johannes N. Plendl and Peter J. Gielisse
Appl. Opt. 4(7) 853-856 (1965)

Lattice Vibrational Spectra and Physical Characteristics of Metals with Cubic Structure

J. N. Plendl, P. J. Gielisse, H. S. Plendl, R. A. Kromhout, and L. C. Mansur
Appl. Opt. 10(6) 1444-1450 (1971)

High-Temperature Spectral Emissivities of H₂O–CO₂ Mixtures in the 2.7-μ Region

C. C. Ferriso and C. B. Ludwig
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The Dielectric and Electrooptical Properties of a Molecular Crystal–Hexamine

G. H. Heilmeier
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