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Optical and electronic properties of mixed Ag-Au tetramer cations
A Shayeghi1, C J Heard2, R L Johnston2
1Eduard-Zintl-Institut, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany.
Abstract:
We present experimental and theoretical studies of the optical response of mixed Ag(n)Au(+)(4-n) (n=1-3) clusters in the photon energy range ℏω = 1.9-3.5 eV. Absorption spectra are recorded by a newly built longitudinal molecular beam depletion spectroscopy apparatus providing lower limits to absolute photodissociation cross sections. The experimental data are compared to optical response calculations in the framework of long-range corrected time-dependent density functional theory with initial cluster geometries obtained by the unbiased Birmingham Cluster Genetic Algorithm coupled with density functional theory. Experiments and excited state calculations shed light on the structural and electronic properties of the mixed Ag-Au tetramer cations.
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