Nonexponential Length Dependence of Molecular Conductance in Acene-Based Molecular Wires.

In the nonresonant regime, molecular conductance decays exponentially with distance, limiting the fabrication of efficient molecular semiconductors at the nanoscale. In this work, we calculate the conductance of a series of acene derivatives connected to gold electrodes using density functional theory (DFT) combined with the nonequilibrium Green's function (NEGF) formalism. We show that these systems have near length-independent conductance and can exhibit a conductance increase with molecular length depending on the connection to the electrodes.

Quantum interference enhances rectification behavior of molecular devices.

We present a theoretical and computational work and demonstrate that cross-conjugated molecules with electron-donating groups are efficient rectifiers with high conductance. The rectification ratios obtained are up to one order of magnitude at an applied bias voltage of 0.3 V.