Experimental Studies of Multiphonon IR Absorption
The temperature dependence of multiphonon absorption in NaF was measured and analyzed in terms of phonon occupation numbers. This procedure allows to decompose the exponential reststrahl absorption wing into N-phonon spectra (N = 2 ... 5) with considerable structure. The latter coincides with phonon combinations with particularly large densities of states. Comparison with data on KBr, NaCl, and LiF demonstrates the influence of zero point motion on the magnitude of multiphonon absorption.
KeywordsOscillator Strength Momentum Conservation Combinational Mode Nominal Transmission Phonon Occupation Number
Unable to display preview. Download preview PDF.
- 5.D.L. Mills and A.A. Maradudin, Phys. Rev. 8: 1716 (1973)Google Scholar
- 8.Supplied by Sonderforschungsbereich 67 an der Universität Stuttgart, Stuttgart, W. Germany; cf. Ref. 6.Google Scholar
- 9.Obtained from the nominal transmission at ≈ > 600 cm−1 where the samples are practically opaque; the values are in agreement with Beckman technical data.Google Scholar
- 12.C. Kittel, Introduction to Solid State Physics, Wiley, New York (1967), p. 98.Google Scholar