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Theoretical study of finite temperature spectroscopy in van der Waals clusters. II Time-dependent absorption spectra

F. Calvo·F. Spiegelman·D. J. Wales
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Abstract

Using approximate partition functions and a master equation approach, we investigate the statistical relaxation toward equilibrium in selected CaAr$_n$ clusters. The Gaussian theory of absorption (previous article) is employed to calculate the average photoabsorption intensity associated with the 4s^2-> 4s^14p^1 transition of calcium as a function of time during relaxation. In CaAr_6 and CaAr_10 simple relaxation is observed with a single time scale. CaAr_13 exhibits much slower dynamics and the relaxation occurs over two distinct time scales. CaAr_37 shows much slower relaxation with multiple transients, reminiscent of glassy behavior due to competition between different low-energy structures. We interpret these results in terms of the underlying potential energy surfaces for these clusters.

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F. Calvo, F. Spiegelman, D. J. Wales. 2002-12-17. Theoretical study of finite temperature spectroscopy in van der Waals clusters. II Time-dependent absorption spectra. https://doi.org/10.1063/1.1566951

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