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Information × Registration Number 0203U000475, 0100U001005 , R & D reports Title The influence of deformation upon energy characteristics of clusters and metal surface popup.stage_title Head Pogosov Valentin, Registration Date 11-02-2003 Organization Zaporizhzhia National Technical University popup.description2 In the framework of classical theory an absorption of small metal particles in the far-infrared is estimated. Reasonable agreement for the calculated and experimental frequency dependences of absorption coefficient of gold, silver and aluminium particles have been obtained. The size dependence of near-infrared absorption is discussed. Analytical expressions for the binding energy of electrons and positrons in dielectric clusters, analysed in this work, is neglected for the elastic effects. Therefore, we present the density-functional theory for neutral liquid clusters that experience the spontaneous deformation. Using the 1/R -expansion, R being the cluster radius, the exact analytical expressions for the size corrections to the chemical potential, surface tension, and atomic density are derived from the condition of mechanical equilibrium. The calculations show significant contribution of self-compression to the binding energy of excess electron - in contrast to positron. The surface stress and the contact potential differences of elastically deformed faces of Al, Cu, Au, Ni, and Ti crystals are calculated within the modified stabilized jellium model using the self-consistent Kohn-Sham method. The obtained values of the surface stress are in agreement with the results of the available first-principal calculations. We find that the work function decreases/ increases linearly with elongation/ compression of crystals. Our results confirm that the available experimental data for the contact potential difference obtained for the deformed surface by the Kelvin method do not correspond to the change of the work function but to the change of the surface potential. The problem of "anisotropy" of the work function and ionization potential of finite sample is discussed. The quantum size oscillations of the energetic quantities and of the elongation force of the gold slabs and wires are calculated in a free-electron model. The isolated slabs and wires as well as the ones in a contact with electrodes are considered applying a simple relation between the Fermi energy and the square-potential-well depth. Treating the electron subsystem of a slab (or wire) in a contact as open one, it is shown that the contact acts like a sort of electron pump which sucks or draws out electrons from a sample. The effect of the contact potential difference on the elastic force oscillations is considered. The calculated amplitudes of force oscillations are in a qualitative agreement with those observed experimentally. Product Description popup.authors popup.nrat_date 2020-04-02 Close