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Photoabsorption Spectra of Na_n+ clusters: Thermal Line-Broadening Mechanisms

M. Moseler·H. Hakkinen·Uzi Landman
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Abstract

Photoabsorption cross sections of small sodium cluster cations (Na$_n^+$, n=3,5,7 and 9) were calculated at various temperatures with the time-dependent local-density-approximation (TDLDA) in conjunction with ab initio molecular dynamics simulations, yielding spectra that agree with measured ones without ad-hoc line broadening or renormalization. Three thermal line-broadening mechanisms are revealed: (I) lifting of level degeneracies caused by symmetry-breaking ionic motions, (II) oscillatory shifts of the entire spectrum caused by breathing vibrations, and (III) cluster structural isomerizations.

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M. Moseler, H. Hakkinen, Uzi Landman. 2001-05-23. Photoabsorption Spectra of Na_n+ clusters: Thermal Line-Broadening Mechanisms. https://doi.org/10.1103/physrevlett.87.053401

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