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    Ground and excited states of Li^-, Be^- through a density-based approach

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    Density functional calculations are performed for ground [He]2s2^2 1^1Se^e, and three metastable bound excited states, 1s2s2p2^2 5^5Pe^e, 1s2p3^3 5^5So^o, 1s2s2p3p 5^5Pe^e of Li^- and [He]2s2p2^2 4^4Pe^e, [He]2p3^3 4^4So^o, 1s2s2p3^3 6^6So^o of Be^- each. The work-function-based exchange potential is used, while the correlation effects are included by employing the Lee-Yang-Parr potential. The relevant nonrelativistic KS equation is solved by means of a generalized pseudospectral discretization scheme offering nonuniform and optimal spatial grid. Computed total energies, radial densities, selected density moments, as well as two transition wavelengths (1s2s2p2^2 5^5Pe^e \to1s2p3^3 5^5So^o of Li^-, [He]2s2p2^2 4^4Pe^e \to [He]2p3^3 4^4So^o of Be^-) show reasonably good agreement with the available theoretical and experimental data. The term energies show an absolute deviation of 0.007--0.171% with the largest deviation being observed for the even-parity 5^5P state of Li^-. The transition wavelengths of Li^-, Be^- are calculated within 0.891 and 0.438% of the experimental values. This offers a simple practical route towards accurate reliable calculation of excited states of anions within density functional theory.Comment: 12 pages, 35 ref

    Mechanisms of Supersymmetry Breaking in the MSSM

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    Preliminary Remarks. Gauge mediated supersymmetry breaking. Gravity mediated supersymmetry breaking. Anomaly mediated supersymmetry breaking. Gaugino mediated supersymmetry breaking. Braneworld supersymmetry breaking. Conclusions.Comment: New references added, minor misprints corrected, text otherwise unchange
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