Rate coefficients for H_2_(v,j)+H_2_(v',j')

Full-dimensional quasiclassical trajectories were calculated using the BMKP2 interaction potential with a minimum of 80000 trajectories at each translational energy. Additional large batches of trajectories were carried out to calculate the cross sections near the threshold to dissociation to attain the desired precision of the rate coefficients.

A piecewise linear excitation function was used to calculate the rate coefficient between 100 and 100000K. The resulting state-specific rate coefficients, {gamma}, were parametrized as a function of temperature over the range 600-10000K using: log_10_{gamma}(t)=a+bz+cz^2^-d(1/t-1) where t=T/4500K and z=log_10_t. The values of the resulting rate coefficients were sensitive to the internal energy of both molecules, with initial vibrational energy having a slightly greater effect than rotational energy.