C59N monomers:: Stabilization through immobilization

C59N is found to sublime in monomer free radical form rather than the more stable dimers, which are normally observed. Using a scanning tunneling microscope operating in ultrahigh vacuum we have found that the monomer form may be immobilized and therefore stabilized on clean Si surfaces. On the less reactive H-terminated Si(100) surface C59N diffuses and forms disordered islands, and a lower limit for the interaction energy between two monomers may be estimated at 0.8 eV. Synchrotron based photoemission experiments have also been performed and show diffusion and redimerization occur for multilayer deposition of C59N.