Ground and excited states of NH_4:Electron propagator and quantum defect analysis

摘要

Vertical excitation energies of the Rydberg radical NH_4 are inferred from ab initio electron propagator calculations on the electron affinities of NH_4~+ .The adiabatic ionization energy of NH_4 is evaluated with coupled-cluster calculations.These predictions provide optimal parameters for the molecular-adapted quantum defect orbital method,which is used to determine Einstein emission coefficients and radiative lifetimes.Comparisons with spectroscopic data and previous calculations are discussed.