Abstract
Static polarizabilities and photoabsorption cross sections of clusters Na −7 , Na8, Na −19 Na20 are calculated, based on the spherical jellium model including the self-interaction correction (SIC) of Perdew and Zunger. To this end, a new formulation of the theory of the linear response is presented, which is suitable for general, self-interaction corrected, many-electron systems. The results obtained display an overall agreement with available experimental data, offering a systematic improvement with respect to the standard TDLDA. Furthermore, the cross sections of the negatively charged clusters are found to be dominated by a broad peak in the visible region, whose line width can be related to the lifetime of the surface plasmon against electron detachment.
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A similar model, denoted by PSIC, and based on the modified Sternheimer equation formalism, has been used in the calculation of static atomic polarizabilities (for details and a survey of references, cf.: Mahan, G.D., Subbaswamy, K.R.: Local density theory of polarizability. New York: Plenum Press 1990
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On leave of absence from the University of Coimbra, Portugal
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Pacheco, J.M., Ekardt, W. A new formulation of the dynamical response of many-electron systems and the photoabsorption cross section of small metal clusters. Z Phys D - Atoms, Molecules and Clusters 24, 65–69 (1992). https://doi.org/10.1007/BF01436605
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DOI: https://doi.org/10.1007/BF01436605