Ground state potential energy surface, 3D time-dependent intramolecular dynamics and vibrational states of the N2H+ molecular ion

The 3D intramolecular dynamics of the N2H+ molecular ion in its electronic ground state is reported. A potential energy surface (PES) is numerically calculated by a multireference configuration interaction method. Employing this PES we calculated the bound-state eigenvalue spectrum of the N2H+ ion by applying the three-dimensional time-dependent wavepacket (WP) method for the total angular momentum J=0. The spectrum is obtained by Fourier transforming the time autocorrelation function of single Gaussian wavepackets initially located in the strong interaction region of the PES. We have carried out time-independent variational calculations to confirm the energy eigenvalues resulting from the WP calculations.