A new strongly-bound chemisorption structure of benzene on Si(100)

Using Scanning Tunneling Microscopy (STM) and ab initio theory we identify a new chemisorbed structure of benzene on Si(100) which we term ‘inter-dimer butterfly,’ ID-BF (C). This involves di-σ-bonding of benzene to two adjacent Si-dimers of a single dimer-row. This configuration is always found in association with a C-type defect, as shown by STM images taken immediately before formation or after elimination of the ID-BF (C) adsorbate. Ab initio calculations yield a binding energy of 2.4 eV for this new structure, higher than the binding energies of other possible chemisorbed configurations of benzene.