Modeling Optical Properties of Small Metallic Nanoparticles Based on Density Functional Theory

Optical properties of silver nanoparticles with different diameters are investigated based on the electronic structures of component silver atoms. Within the frame of tight binding method, the local density of states of each silver atom is obtained through a recursive approach that extracts the required information directly from the Hamilton matrix. Then the interaction between the electric field of incident light and electrons in the nanoparticles is simulated to characterize their optical features and the size effects were interpreted according the results.

Quadrupole Hyperfine Structure in the Rotational Spectra of Sulfur Dichloride

The nuclear quadrupole coupling of [35Cl,35Cl]- and [35Cl,Cl]-sulfur dichloride was investigated using waveguide microwave Fourier transform (MWFT) spectroscopy. The analysis was performed with direct diagonalization of the Hamilton matrix. Due to some measured transitions with near degeneracy it was possible to determine the off diagonal elements χab of the quadrupole coupling tensor with high accuracy. S35Cl2: χ aa (35Cl1) = χaa(35Cl2) = -38.671(11) MHz, χcc(35Cl1) = χcc(35Cl2) = 47.7945(66) MHz, χab(35Cl1) = -χab( Cl2) = ± 53.76(23) MHz. S35Cl36Cl: χaa(35Cl) = -37.756(13) MHz, χcc(35Cl) = 47.7915(75) MHz, χab(35Cl) = ± 54.018(83) MHz, χ aa(35Cl) = -31.217(13) MHz, χcc (37Cl) = 37.6759(66) MHz, χab ( 37 Cl ) = + 42.285(98) MHz. We also determined the quadrupole coupling constants in their principal axes system. In comparison with the restructure the z-axis of the coupling tensor was found to be tilted 1.3° out of the S - Cl bond axis