Ultrathin lead films on metallic and semiconductor substrates are technologically demanded and actively studied by different experimental and theoretical methods. The formation of these films gives rise to new adsorbate-induced electron states and vibrational modes. The dynamical properties of atoms on surfaces depend sensitively on their bonding environment and thus provide valuable insight into the local geometry and chemical bonding at the boundary of a solid.
View Article and Find Full Text PDFThe interplay of the atomic structure and phonon spectra in a variety of two dimensional phases forming during submonolayer Pb adsorption on a Cu(001) surface has been investigated using embedded atom method interatomic interaction potentials. Complementary calculations of the equilibrium atomic structure of these phases were performed using density functional theory. It has been shown that the dynamic stability of the Pb/Cu(001) structures increases with increasing the coverage from 0.
View Article and Find Full Text PDFPhys Chem Chem Phys
April 2021
The structure and magnetic properties of small Cr clusters, Cr and Cr, adsorbed on the Cu(111) surface have been investigated using density functional theory (DFT) calculations and their vibrational properties have been studied within calculations based on tight-binding second moment approximation interatomic interaction potentials (TBSMA). It has been shown that the magnetic ordering in the Cr clusters significantly affects their crystal structure and symmetry, which influences the vibrational modes of the clusters and nearest neighbor copper atoms. In turn, these modes select potentially possible structures of Cr and Cr, prohibiting the lowest total energy cluster structure as dynamically unstable.
View Article and Find Full Text PDFWe present a theoretical investigation of the structural and vibrational properties of ordered 2D phases formed by the Li, Na and K atoms on the Cu[Formula: see text] surface. The lattice relaxation, phonon dispersions and polarization of vibrational modes as well as the local density of states are calculated using the embedded-atom method. The obtained structural parameters and vibrational frequencies are in close agreement with available experimental results.
View Article and Find Full Text PDFCollective vibrational modes of crystal lattices, called phonons, determine fundamental material properties, such as their thermal and electrical conductivities. Bulk phonon spectra are influenced by point defects. More recently, the importance of phonons on nanostructures has come into the focus of attention.
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