Electrical characterization of C28 fullerene junctions formed with group 1B metal electrodes

Abstract

We present an atomistic theory of electronic transport through single molecular junctions based on smallest stable fullerene molecule, C28. The electronic properties of single molecular junctions critically depend on the nature of electrode material. The two probe device is modeled by constraining C28 between two semi-infinite metal electrodes, from group 1B of periodic table, copper, silver and gold. We have highlighted the correlated phenomena of resonant conduction and current driven dynamics in molecular junctions using extendend Huckel theory in combination with non equilibrium Green’s function framework. We conclude strong dependence of conductance on transmissions, which leads to oscillating conductance spectrum. An interesting interplay between conducting channels and different degrees of spatial localization and delocalization of molecular orbitals is evinced. The physical origin of current and conductance of so-formed C28 molecular junctions is discussed in detail by analysing their density of states, transmission spectra, molecular orbital analysis, rectification ratio and molecular projected self consistent Hamiltonian eigen states at different operating voltages ranging from -2V to +2V.