We develop a general method to study ultrafast laser induced charge migration in molecules which includes both electronic and nuclear dynamics. The method can be applied to relatively large systems. Detailed analysis of charge migration in pyrene is performed. Decoherences and recoherences of charge migration in pyrene are found and explained in terms of nuclear motions.

We report ultrafast charge migration in ionized iodo-alkyne chain I(CC) nH+ for n = 1, 2, …, 5. The dynamics of electron density become more complicated with the increasing length of the molecular chain. However, the essential properties of charge migration in I(CC) nH+ can be clearly interpreted in terms of the electron flux. By systematic investigations of the dynamics of electron density, hole density, and the electron flux for different molecules, the size dependence of charge migration in I(CC) nH+ is discussed.