Direct ab initio molecular dynamics study of NO2++(H2O)4→HNO3(H7O3+)

Direct ab initio molecular dynamics has been employed to simulate collisions between NO2+ and a water tetramer to produce HNO3(H7O3+). Trajectory energies were evaluated at the MP2/6-31+G* level. Reactive trajectories reveal a set of concerted motions leading to proton transfer and HNO3 formation. No energy barrier was found in the entrance channel which leads to NO2+(H2O)4 complexes nearly energetically degenerate with HNO3(H7O3+).