Knowledge Bank

The C10 molecule is presently thought to be important in stratospheric pollution studies because its reaction with oxygen atoms completes the catalytic cycle which results in a depletion of ozone by free C1. We are presently considering another possible fate of C10, namely, predissociation in the $A2\Pi$ state which leads to ground state atoms. If this process is sufficiently fast, its overall effect will be to lower the predicted amount of ozone depletion owing to the presence of C1-bearing compounds in the stratosphere. In the course of this study all potential curves which correlate to the $O(3P)+Cl(2P)$ and $O(1D)$ and $Cl(2P)$ atomic limits have been computed. The calculations were performed with large MCSCF + CI wavefunctions which employed 47 Slater type orbitals in the basis set and $10\sigma$, $5\Pi$, and $2\delta$ molecular orbitals. These calculations predict values for the ground state dissociation energy, dipole moment, and the $X2\Pi -A2\Pi$ separation that are in good agreement with experiment. The results are of sufficient quality that they should enable an identification of the processes which cause the massive predissociation known to occur in the $A2\Pi$ state.