A Single Molecule Kondo Switch: Multistability of Tetracyanoethylene on Cu(111)
journal contributionposted on 13.10.2010, 00:00 by Taeyoung Choi, Stéphane Bedwani, Alain Rochefort, Chia-Yi Chen, Arthur J. Epstein, Jay A. Gupta
Single tetracyanoethyelene (TCNE) molecules on Cu(111) are reversibly switched among five states by applying voltage pulses with the tip of a scanning tunneling microscope. A pronounced Kondo resonance in tunneling spectroscopy indicates that one of the states is magnetic. Side bands of the Kondo resonance appear at energies which correspond to inter- and intramolecular vibrational modes. Density functional theory suggests that molecular deformation changes the occupancy in TCNE’s molecular orbitals, thus producing the magnetic state.