The kinetics of the surface adsorption and desorption processes were simulated based on the quantum-chemical results. The adsorption rate was approximated from the impingement rate as no tight transition state is present along the internal reaction coordinate. The reverse reaction rates were derived based on the forward reaction rates to ensure that the thermodynamic equilibria can be reached as enough time has passed. The DFT-based surface reaction rates together with the gas phase reaction mechanism and rate for C2H6 formation from CH3 from literature were employed in the kinetic model. The simulation of the kinetics was performed using the MATLAB SimBiology module . The simulations of the amount of surface species as a function of time start from the surface fully covered by methyl groups (4CH3(s)) at the pressure 100 pascal and the temperature 773 Kelvin. The pressure was held constant by the presence of non-interacting gas molecules (e.g. N2) plus molecules formed after desorption. The number of gas molecules was assumed to be much larger than the number of surface sites, i.e. the initial molar ratio of gas molecules/CH3(s) was set to 50. Two kinetic models are considered here. In the first model, the methyl radicals produced from the reactions are assumed to be completely purged away from the system at all times (i.e. by setting their adsorption rate to zero) similar to when H2, N2 or Ar is introduced between the TMA and NH3 pulse in the ALD cycle, while in the second model no extra pulse is used, i.e. no extra pulse between TMA and NH3 is assumed.