Density functional theory calculations have been carried out to investigate the effect of the atomic under-coordination on
the bond contraction, lattice strain, and electron configuration of Cuboctahedral and Marks decahedral structures of
silver and copper nanoclusters. Our calculated results are consistent in trend with experimental measurements including
extended X-ray-absorption fine structure (EXAFS), scanning tunneling microscope/spectroscopy (STM/S), X-ray
photoelectron spectroscopy (XPS), and ultraviolet photoelectron spectra (UPS). This agreement approved the
prognostications made on the bond-order-length-strength (BOLS) correlation and nonbonding electron polarization
(NEP), suggesting that atomic under-coordination at the surface of nanoclusters cause bond contraction, which then leads
to lattice strain, charge densification, core electron entrapment, as well as polarization of valence charge. The results of
this work will contribute to the understanding of the intriguing properties of Ag and Cu nanoclusters.
We have considered a two dimensional narrow semiconductor ring with sectorial barriers that is threaded by
magnetic flux. Using numerical diagonalization techniques, we have presented the diagrams of the energy spectra
versus the magnetic flux. For a constant value of the barrier height, with enhancement of the number of barriers, the
energy levels shift to higher energies and the degeneracy of the system increases. We have also investigated the
behavior of the energy levels with the magnetic flux for different values of the barrier height. The fluctuation of the
energy levels decreases, as the barriers' height increases.