Electronic transport properties of tetracyclopentadienyl modified with C and Si atoms

The electronic transport characteristics for three tetracyclopentadienyl systems with C and Si atoms have been investigated on the basis of density-functional theory and non-equilibrium Green's function. Ohmic conductance, current-voltage curves, and differential conductance are obtained and analyzed. Switch and negative differential resistance behavior is observed in these systems. The novel characteristics of these systems are attributed to the highest occupied molecular orbital and lowest unoccupied molecular orbital and to the change in transmission spectra within the bias range.