We present a simple non-self-consistent method for the calculation of the molecular conductance under finite bias voltage. Our approach is applied to a molecular photoswitch that has recently been investigated in break junction experiments [D. Dulić et al., Phys. Rev. Lett. 91, 207402 (2003)]. We obtain $I\text{−}V$ characteristics that are qualitatively in agreement with experimental measurements. Employing our electronic structure calculations, we provide a detailed explanation for the switching behavior observed in experiment.

• Received 25 January 2005

DOI:https://doi.org/10.1103/PhysRevB.72.073104