FEMTOSECOND PROBING OF MOLECULAR-DYNAMICS BY MASS-SPECTROMETRY IN A MOLECULAR-BEAM

Femtosecond probing of molecular dynamics using mass-spectrometry in a molecular beam is reported. The probing is made using multiphoton ionization of a skimmed molecular beam followed by time-of-flight ion detection. Studies of CH3I, CD3I and I2 have been made, and here we report our observation of wave-packet motion, the vibrational and rotational dynamics, and the femtosecond predissociation dynamics of Rydberg states. The mass-selection makes it now possible to study fragmentation and ionization on the femtosecond time scale.