Abstract
Size-evolutions of structural and spectral properties in two types of finite systems are discussed. First we focus on energetics and structures of gold clusters, particularly Au N in the 40 ≲ N ≲ 200 range exhibiting a discrete sequence of optimal clusters with a decahedral structural motif, and on the electronic structure of bare and methyl-thiol passivated Au38 clusters. Subsequently, bonding and spectra of quanturn dot molecules (QDM’s) are investigated, using a single-particle two-center oscillator model and the local-spin-density (LSD) method, for a broad range of interdot distances and coupling strengths. A molecular orbital classification of the QDM states correlates between the united-dot and separated-dots limits. LSD addition energies and spin polarization patterns for QDM’s in the entire coupling range are analyzed, guiding the construction of a constant interaction model. A generalization of the non-interacting-electrons Darwin—Fock model to QDM’s is presented. Wigner crystallization of the electrons leading to formation of Wigner supermolecules is explored in both the field-free case and with a magnetic field using a spin-andspace unrestricted Hartree—Fock Method.
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Barnett, R.N., Cleveland, C.L., Häkkinen, H., Luedtke, W.D., Yannouleas, C., Landman, U. (1999). Structures and spectra of gold nanoclusters and quantum dot molecules. In: Châtelain, A., Bonard, JM. (eds) The European Physical Journal D. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-88188-6_19
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DOI: https://doi.org/10.1007/978-3-642-88188-6_19
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