Trajectory studies of unimolecular reactions of Si2H4 and SiH2 on a global potential surface fitted to a b i n i t i o and experimental data

The unimolecular decomposition dynamics of Si2H4 have been investigated using classical trajectory methods on a global potential-energy surface fitted to the results of ab initio calculations and the available experimental data. The required phase-space averages are computed using Metropolis sampling techniques. It is found that unless the parameters of the Markov walk are adjusted for each different type of atom present, extremely long Markov walks are required to adequately cover the phase space of the system. Microcanonical rate coefficients for the decomposition of Si2H4 into all open channels are reported at energies in the range 5.0