Hydrogen dissociation over Au nanowires and the fractional conductance quantum.
The dissociation of H2 molecules over stretched Au nanowires and its effect on the conductance are analyzed using a combination of density functional theory (DFT) total energy calculations and nonequilibrium Keldysh-Green function methods. Our DFT simulations reproduce the characteristic formation of Au monatomic chains with a conductance close to G0=2e2/h. These stretched Au nanowires are shown to be better catalysts for dissociation than Au surfaces. This is confirmed by the nanowire conductance evidence: while insensitive to molecular hydrogen, atomic hydrogen induces the appearance of fractional conductances (G approximately 0.5G0) as observed experimentally.
Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, Madrid E-28049, Spain. jelinekp@fzu.cz
Pavel
P
Jelínek
Rubén
R
Pérez
José
J
Ortega
Fernando
F
Flores