The Electronic Transparence of a Single C60 Molecule

We report the first study of electrical contact with an individual molecule (C60). Using an STM tip, the electrical current I flowing as a function of tip displacement s towards the molecule is investigated (I(s) characteristics). The tunneling current increases approximately exponentially with tip displacement in the tunnel regime, but this behavior changes significantly as contact is established. From the I(s) data and calculations for C60 we determine an apparent electrical resistance of 54.80 MOhms for the junction at ``tip contact''. In the Landauer formalism, this value
is a measurement of the electronic transparence 2.35 x 10**-4 of the molecule under the tip.