Renormalized molecular levels in a (formula presented) molecular electronic device

Abstract

We address several general questions about quantum transport through molecular systems by an ab initio analysis of a scandium-nitrogen doped (formula presented) metallofullerene device. Charge transfer from the (formula presented) is found to drastically change the current-voltage characteristics: the current through the (formula presented) device is double that through a bare (formula presented) device. We provide strong evidence that transport in such molecular devices is mediated by molecular electronic states which have been renormalized by the device environment, such as the electrodes and external bias (formula presented) The renormalized molecular levels and main transmission features shift in energy corresponding to half the applied bias voltage. This is also consistent with our finding that the voltage drops by (formula presented) at each molecule/electrode contact. © 2001 The American Physical Society.