field ionization

Field ionization is a method used in mass spectrometry to create ions from molecules. This process involves applying intense electric fields, on the order of 10⁸ volts per centimeter, near sharp points or edges of electrodes. When organic compounds in vapor form are introduced into these intense fields, they become ionized. A key advantage of field ionization is that the ions are formed with very little excess energy, which minimizes fragmentation of the molecular ions. This characteristic makes it easier to determine the molecular formulas of the compounds being analyzed. Field ionization is also related to field emission, where electrons are discharged from a material's surface under a strong electric field.12