Quenching of O(1D2) by Cl2CO: kinetics and O(3PJ) yield

Absolute rate coefficients (k1) for the deactivation of electronically excited oxygen atoms, O(1D2), by phosgene (Cl2CO) have been measured as a function of temperature over the range 194– 425 K. The results are well described by the Arrhenius expression k1(T)=2.04×10−10exp(+27/T) cm3 molecule−1 s−1. The reported values for k1(T) are considerably lower than the values currently recommended for use in modeling stratospheric chemistry. The yield of ground state oxygen atoms, O(3PJ), is found to be 0.20±0.04.