Electric field assisted thermal desorption ionization using an infrared laser

A new technique has been developed for the formation of gas-phase electrons and ions by electric field assisted thermal desorption ionization at atmos pheric pressure. Experiments were carried out using a sharp tungsten wire t ip coated with a thin solid sample film which was irradiated by a 10.6 mu m infrared laser. By applying a strong electric field on the laser-irradiate d tungsten wire tip, abundant ions such as alkali ions, halide ions, and al so multiply charged negative ions S2O62- and S2O82-, were formed. Copyright (C) 1999 John Wiley & Sons, Ltd.