Orientational dependence of current through molecular films - art. no. 195413

We study the current through molecular films as a function of the orientati on of the molecules in the film with respect to electrodes. It may change b y more than an order of magnitude, depending on the angle between the axis of the molecules and the normal to the electrode. This is a consequence of a strong directional character of p orbitals that determine the conductance through the conjugated molecules. We demonstrate this result on an exactly solvable model, and present the calculations for two different experimenta lly accessible molecular films sandwiched between gold electrodes.