We present a synchrotron-radiation photoemission study of the different adsorption states for benzene on cleaved Si(111) substrates at room temperature and low temperature. The results provide information on the chemisorption or physisorption nature of the adsorption states. In particular, the data suggest that physisorption and chemisorption states coexist at low temperature and low coverage.

• Received 17 November 1986

DOI:https://doi.org/10.1103/PhysRevB.35.9218