Electronic quenching of N(2D) in collision with CO(1Σ+) via spin-forbidden transitions

Abstract

In nitrogen-rich atmospheres under extreme conditions, the N2 molecule dissociates into atomic nitrogen in different electronic states. In particular, N(2D) is known to be reactive and to drive a complex chemistry in such regimes. If the atmosphere also contains carbon monoxide (such as Earth and Mars), several collisional processes with nitrogen-, carbon-, and oxygen-bearing species are relevant. Here, we employ a set of three accurate and global potential energy surfaces for the CNO system to study the N(2D) + CO → N(4S) + CO electronic quenching process, using the quasiclassical trajectories approach coupled with two different surface hopping schemes. Experimental measurements of the quenching rate coefficient are available only at room temperature, and our computational predictions show good agreement. We further provide the temperature dependence of the rate coefficients for the first time, extending to the hyperthermal regime. The effect of the initial rovibrational state of CO on the reactivity, as well as the distribution of energy in the products, is also unveiled.