Narrow Results

The harmonic emissions from hydrogen molecular ion at different initial vibrational states have been simulated by numerically solving the time-dependent Schrödinger equation. The results show that the nuclear motion exhibits different effects on the spectral structure for different vibrational states. For lower vibrational state, the odd harmonics experience obvious harmonic shifting; however, for higher vibrational state, the even harmonics are emitted from the symmetric system due to the asymmetric electronic distribution in the coupling region of two lowest electronic states.