Ion-pair dissociation of N2O in the 16.25–16.41eV: Dynamics and electronic structure

The ion-pair dissociation dynamics of N2O→XUVN2+(XΣg+2,υ)+O−(Pj2) at 16.248, 16.271, 16.389, and 16.411eV have been studied using the velocity map imaging method and tunable XUV laser. The electronic structures of the ion-pair states have been studied by employing the ab initio quantum chemical calculation. The translational energy distributions and the angular distributions of the photofragments have been measured. The results show that about 40% of available energies are transformed into the translational energies, and the first excited vibrational states are populated most strongly for all four excitation energies. The anisotropy parameters β are ∼1. The ab initio calculations at the level of CASSCF∕6-311++g(3df) show that the equilibrium geometries of the ion-pair states are nonlinear with bond lengths R(N–N)=1.10A, R(N–O)=2.15A, and bond angle N–N–O=103°, respectively. The ion-pair states are formed by electron migration from the bonding σ orbital of NN to the antibonding σ orbital localized primari...