Abstract
Static polarizabilities and optical absorption spectra of ground state structures of clusters are investigated from first principles within static and time-dependent density functional theory. The static polarizabilities of the clusters with less than 7 atoms exhibit even-odd oscillations. The polarizabilities of and are very close and noticeably lower. This change in the behavior of the static polarizability is correlated with the transition from two-dimensional to three-dimensional structures at . The optical spectra calculated within the time-dependent local density approximation indicate sharp excitations in the 3–5 eV region. These are associated mainly with electrons, although electrons also affect the spectra by quenching the oscillator strengths through screening of the electrons and by getting partially involved in the excitations. The calculated optical spectra are in good agreement with the available experimental data and results from earlier theoretical studies.
- Received 13 June 2005
DOI:https://doi.org/10.1103/PhysRevB.72.085445
©2005 American Physical Society