n-Heptane is the most important straight chain paraffin in the fossil-fuel industry.In this work,pyrolysis of nheptane at high temperature is investigated by a series of ReaxFF based reactive molecular dynamic simulations.The pyrolysis correlated intermediate reactions,important product/intermediate distributions,and corresponding kinetics behaviors are systematically analyzed at atomistic level.The results indicate that the entire pyrolysis process is radicaldominated.The unimolecular dissociation is the main pathway of n-heptane decomposition.Initiation of the decomposition is mainly through C-C bond fission.Central C-C bonds would dissociate prior to the terminal ones.Besides,the Rice-Kossiakoff theory is proved for the pyrolysis of n-heptane at the atomistic level.To give a better description of the pyrolysis behavior,some alkane related intermolecular reactions should be considered in the mechanism.The apparent activation energy extracted from the present simulations is 43.02-54.49 kcal/mol in the temperature range 2400-3000 K,which is reasonably consistent with the experimental results.