Abstract

The cluster-continuum approximation of the method of thermodynamic functionals of the internal structural coordinates is used to carry out a theoretical structural-thermodynamic analysis of the relationship between the half-width and the position of the absorption-band maxima in the low-frequency IR spectra of liquid systems. By considering the thermodynamic theory of fluctuations, it is shown that this relationship is strictly functional and is determined by the ratio of the effective cluster heat capacities or of the generalized thermodynamic susceptibilities in the ground and excited states. For molecular liquids, it follows from this theory that the half-width is directly proportional to the position of the low-frequency IR absorption-band maxima, with a slope close to unity.

Absorption cross-section maxima and minima in IR absorption bands of small ionic ellipsoidal particles

Craig F. Bohren and Donald R. Huffman
Appl. Opt. 20(6) 959-962 (1981)

Water cluster interpretation of IR absorption spectra in the 8–14-μm wavelength region

S. H. Suck, J. L. Kassner, and Y. Yamaguchi
Appl. Opt. 18(15) 2609-2617 (1979)

Products of Strength Times Self-Broadened Half-Widths of Absorption Lines in the ν₂ Band of Water Vapor

D. K. Prinz
Appl. Opt. 7(4) 689-693 (1968)

Relationship between Critical Flicker-Frequency and a Set of Low-Frequency Characteristics of the Eye

H. de Lange Dzn
J. Opt. Soc. Am. 44(5) 380-389 (1954)

Liquid Structures and Glass Formation*

W. A. Weyl
J. Opt. Soc. Am. 53(4) 407-409 (1963)