A. Bagrets

Transport properties of individual C60-molecules

Electrical and thermal transport properties of C60 molecules are investigated with density-functional-theory based calculations. These calculations suggest that the optimum contact geometry for an electrode terminated with a single-Au atom is through binding to one or two C-atoms of C60 with a tendency to promote the sp(2)-hybridization into an sp(3)-type one. Transport in these junctions is primarily through an unoccupied molecular orbital that is partly hybridized with the Au, which results in splitting the degeneracy of the lowest unoccupied molecular orbital triplet. The transmission through these junctions, however, cannot be modeled by a single Lorentzian resonance, as our results show evidence of quantum interference between an occupied and an unoccupied orbital. The interference results in a suppression of conductance around the Fermi energy. Our numerical findings are readily analyzed analytically within a simple two-level model.

C58 on Au(111): A scanning tunneling microscopy study

C58 fullerenes were adsorbed onto room temperature Au(111) surface by low-energy (~6 eV) cluster ion beam deposition under ultrahigh vacuum conditions. The topographic and electronic properties of the deposits were monitored by means of scanning tunnelling microscopy (STM at 4.2 K). Topographic images reveal that at low coverages fullerene cages are pinned by point dislocation defects on the herringbone reconstructed gold terraces (as well as by step edges). At intermediate coverages, pinned monomers act as nucleation centres for the formation of oligomeric C58 chains and 2D islands. At the largest coverages studied, the surface becomes covered by 3D interlinked C58 cages. STM topographic images of pinned single adsorbates are essentially featureless. The corresponding local densities of states are consistent with strong cage-substrate interactions. Topographic images of [C58]n oligomers show a stripe-like intensity pattern oriented perpendicular to the axis connecting the cage centers. This striped pattern becomes even more pronounced in maps of the local density of states. As supported by density functional theory, DFT calculations, and also by analogous STM images previously obtained for C60 polymers [M. Nakaya, Y. Kuwahara, M. Aono, and T. Nakayama, J. Nanosci. Nanotechnol. 11, 2829 (2011)], we conclude that these striped orbital patterns are a fingerprint of covalent intercage bonds. For thick C58 films we have derived a bandgap of 1.2 eV from scanning tunnelling spectroscopy data confirming that the outermost C58 layer behaves as a wide band semiconductor.

Kondo effect in binuclear metal-organic complexes with weakly interacting spins

We report a combined experimental and theoretical study of the Kondo effect in a series of binuclear metal-organic complexes of the form

Electrical control over the Fe(II) spin crossover in a single molecule: Theory and experiment

[{(\mathrm{Me}(\mathrm{hfacac})}_{2}{)}_{2}(\mathrm{bpym})]{}^{0}

Electrochemical gate-controlled electron transport of redox-active single perylene bisimide molecular junctions

, with Me = nickel (II), manganese (II), zinc (II); hfacac = hexafluoroacetylacetonate, and bpym = bipyrimidine, adsorbed on Cu(100) surface. While Kondo features did not appear in the scanning tunneling spectroscopy spectra of nonmagnetic

Electron-Vibration Interaction in the Presence of a Switchable Kondo Resonance Realized in a Molecular Junction

{\mathrm{Zn}}_{2}

C₅₈ on Au(111): an STM-based study

, a zero bias resonance was resolved in magnetic

Signatures of spin related effects in electron transport characteristics of single molecules

{\mathrm{Mn}}_{2}

Correlation effects and magnetism in transport through single molecules

and

Electrical control over the Fe(II) spin-crossover and magnetoresistance effect at a single molecule level

{\mathrm{Ni}}_{2}