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H$_2$ dissociation over Au-nanowires and the fractional conductance quantum

Pavel Jelinek·Ruben Perez·Jose Ortega·Fernando Flores
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Abstract

The dissociation of H$_2$ molecules on stretched Au nanowires and its effect on the nanowire conductance are analyzed using a combination of Density Functional (DFT) total energy calculations and non-equilibrium Keldish-Green function methods. Our DFT simulations reproduce the characteristic formation of Au monoatomic chains with a conductance close to % the conductance quantum $G_0 = 2e^2/h$. These stretched Au nanowires are shown to be better catalysts for H$_2$ dissociation than Au surfaces. This is confirmed by the nanowire conductance evidence: while not affected practically by molecular hydrogen, atomic hydrogen induces the appearance of fractional conductances ($G \sim 0.5 G_0$) as observed experimentally.

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Pavel Jelinek, Ruben Perez, Jose Ortega, Fernando Flores. 2005-10-19. H$_2$ dissociation over Au-nanowires and the fractional conductance quantum. https://doi.org/10.1103/physrevlett.96.046803

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