An investigation of the hydrogenation of aromatic hydrocarbons to yield saturated cycloalkanes: relevance to graphite-diamond transformation

Abstract

Step-wise hydrogenation of benzene, naphthalene and pyrene to yield the corresponding saturated derivatives has been examined at the AM1/RHF level in order to understand the graphite-diamond conversion in a hydrogen plasma. Hydrogenation of these aromatics proceeds readily with a negligible activation barrier, suggesting that saturation of a graphite surface by interaction with hydrogen atoms is likely to be very facile. Addition of CH3. and C2H. radicals to a partially saturated hydrocarbon is shown to yield adamantane, which can act as the nucleation site for diamond growth, a situation that also obtains with partially hydrogenated graphite.