Dissociation of Hydrogen Molecules by Vibrational Excitation and Three-Body Recombination Coefficient. II

The recombination of two hydrogen atoms in the presence of a third in a thermal collision is considered, the principle of detailed balance being used to obtain the three-body coefficient $C_3$ from the cross section ${\sigma }_2$ of the reverse, dissociation process. This cross section is calculated by a method developed previously which depends on correcting the Born approximation by means of the exact one-dimensional problem. We consider the case when the molecule is formed in a highly excited vibrational state of the electronic ground state and the excess energy of several $\mathrm{kT}$ goes into translational energy of the third atom. The three-body coefficient in this case is of order 3×${10}^{-36\mathrm{}}$ ${\mathrm{cm}}^6$ ${\sec }^{-1\mathrm{}}$, which is still much smaller than the empirical values. Some estimate is made of the validity of the correction method.