Abstract: A three dimensional (3D) time-dependent wave-packet method has been used to solve the Schrdinger equation of an electron coupled with the nucleus. The re-collision probabilities between the electron and the D+2 have been derived, and we find that most D+2 ions come from the first re-collision between the electron and its parent ion D+2 in the first optical period. Our calculation is in good agreement with experimental results. The quantum dynamics method to track the motion of both electron and nuclear wave packets with attosecond resolution is described.