Effects of the molecule-electrode interface on the low-bias conductance of Cu–H{sub 2}–Cu single-molecule junctions
- Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University, Beijing 100871 (China)
- School of Physics, AMBER and CRANN Institute, Trinity College, Dublin 2 (Ireland)
The atomic structure and electronic transport properties of a single hydrogen molecule connected to both symmetric and asymmetric Cu electrodes are investigated by using the non-equilibrium Green’s function formalism combined with the density functional theory. Our calculations show that in symmetric Cu–H{sub 2}–Cu junctions, the low-bias conductance drops rapidly upon stretching, while asymmetric ones present a low-bias conductance spanning the 0.2–0.3 G{sub 0} interval for a wide range of electrode separations. This is in good agreement with experiments on Cu atomic contacts in a hydrogen environment. Furthermore, the distribution of the calculated vibrational energies of the two hydrogen atoms in the asymmetric Cu–H{sub 2}–Cu junction is also consistent with experiments. These findings provide clear evidence for the formation of asymmetric Cu–H{sub 2}–Cu molecular junctions in breaking Cu atomic contacts in the presence of hydrogen and are also helpful for the design of molecular devices with Cu electrodes.
- OSTI ID:
- 22679058
- Journal Information:
- Journal of Chemical Physics, Vol. 145, Issue 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
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