Characteristics of photoelectrons emitted in matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance experiments

We show a simple method to study the characteristics of electrons emitted from the metal target in matrix-assisted laser desorption/ionization (MALDI) experiments. The method is based on measurements of SF6- ion appearance curves by introducing SF6 as a buffer gas into the vacuum chamber during laser desorption. We obtained the energy distribution of emitted electrons, as well as information on their origin and on ion formation mechanisms in MALDI experiments.