Quantum transport of the single metallocene molecule

Highlights: • The metallocen molecules structure become stretched along the transport direction. • The nickelocene molecule have a lager conductance. • Negative differential resistance is found in the ferrocene, cobaltocene molecules. The Quantum transport of three single metallocene molecule is investigated by performing theoretical calculations using the non-equilibrium Green's function method combined with density functional theory. We find that the three metallocen molecules structure become stretched along the transport direction, the distance between two C_p rings longer than the other theory and experiment results. The lager conductance is found in nickelocene molecule, the main transmission channel is the electron coupling between molecule and the electrodes is through the Ni d_xz and d_yz orbitals and the s, d_xz, d_yz of gold. This is also confirmed by the highest occupied molecular orbital resonance at Fermi level. In addition, negative differential resistance effect is found in the ferrocene, cobaltocene molecules, this is also closely related with the evolution of the transmission spectrum under applied bias.