Imaging isodensity contours of molecular states with STM

Abstract

We present an improved way for imaging the density of states of a sample with a scanning tunneling microscope, which consists in mapping the surface topography while keeping the differential conductance (d I /d V ) constant. When archetypical C _60 molecules on Cu(111) are imaged with this method, these so-called iso-d I /d V maps are in excellent agreement with theoretical simulations of the isodensity contours of the molecular orbitals. A direct visualization and unambiguous identification of superatomic C _60 orbitals and their hybridization is then possible.

Keywords

• scanning tunneling microscopy
• scanning tunneling spectroscopy
• fulleren
• C60
• super-atomic orbitals