【Abstract】 The multiphoton ionization (MPI) of diethylamine is first reported in this paper. Atime-of-flight mass spectrometer was used in the experiment under collision-free condition. MPImass spectra were measured in the region of 464 ～486 nm using a dye laser and at double fre-quency of a Nd:YAG laser. Molecular ion was created through resonance enhanced multiphotonionization (REMPI) via Rydberg states. Fragment, ion distribution was formed through “lladderswitching” process. The experimentai demonstration of the process is reported for the first timeby the discussion of dependence of ion relative, abundance on laser wavelength and energy. Thecompetition bet,ween further up-pumping and fragmentation of Parent ion also exists, and higherlaser intensity favors the former.更多还原