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تسجيل مستخدم جديدAn ab initio non-equilibrium Greens function approach to charge transport: dithiolethine
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We present a novel ab initio non-equilibrium approach to calculate the current across a molecular junction. The method rests on a wave function based full ab initio description of the central region of the junction combined with a tight binding approximation for the electrodes in the frame of the Keldysh Greens function formalism. Our procedure is demonstrated for a dithiolethine molecule between silver electrodes. The main conducting channel is identified and the full current-voltage characteristic is calculated.
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We present a novel ab initio non-equilibrium approach to calculate the current across a molecular junction. The method rests on a wave function based description of the central region of the junction combined with a tight binding approximation for th
e electrodes in the frame of the Keldysh Greens function formalism. In addition we present an extension so as to include effects of the two-particle propagator. Our procedure is demonstrated for a dithiolbenzene molecule between silver electrodes. The full current-voltage characteristic is calculated. Specific conclusions for the contribution of correlation and two-particle effects are derived. The latter are found to contribute about 5% to the current. The order of magnitude of the current coincides with experiments.
The electronic structure of organic-inorganic interfaces often feature resonances originating from discrete molecular orbitals coupled to continuum lead states. An example are molecular junctions, individual molecules bridging electrodes, where the s
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