Comment on "on the electron affinity of nitromethane (CH 3NO2)"

Nitrogen dioxide, NO2, being a stable free radical is a reactive gaseous species that is well-known as an anthropogenic pollutant; it is the major initiator of photochemical smog in the troposphere and is an ozone-depleting agent in the stratosphere.(1) Recently, following the successful multireference ab initio determination of an accurate value for the adiabatic electron affinity (AEA) of nitromethane, CH3NO2,(2) it has come to our attention that a similar high-level multiconfigurational convergence of theory and experiment has not been reported for NO2. The previous CH3NO2 study utilizing the N-state multiconfigurational quasi-degenerate perturbation theory of second order method, NS-MCQDPT,(3) showed that for CH3NO2 electron capture is dominated by the -NO2 group, and the level of theory in that study should also apply to gas-phase NO2.