Mechanical Effects on the Electronic Properties of a Biphenyl Based Molecular Switch

MARTIN E. ZOLOFF MICHOFF; M. EZEQUIEL CASTILLO; EZEQUIEL P. M. LEIVA

JOURNAL OF PHYSICAL CHEMISTRY C

AMER CHEMICAL SOC

Lugar: Washington; Año: 2015 vol. 119 p. 5090 - 5097

1932-7447

Using a combination of density functional theory and non-equilibrium Green function calculations, the effect of mechanically stretching a biphenyl-based molecular switch bonded to Au electrodes is studied. Thermodynamic and transport properties of the high and low conducting species are analyzed. A disulfide functionality bridging the aromatic rings is used to switch between the high and low conducting species. The potential of such a system as a molecular device has already been proved [J. Phys. Chem. C 2013, 117, 25724]. Mechanically stretching the molecular junction has major effects on both the thermodynamics of the switching reaction and the conductance ratio between the high and low conducting species involved in the molecular switch. It is also shown that the conductance of each individual species can be modulated by means of an external mechanical force, thus providing a dual switching mechanism for the proposed system.