fast atom bombardment


fast atom bombardment

A technique of mass spectrometry that uses a beam of neutral atoms (created by neutralising ions of about 5 keV energy) to sputter sample molecules from a liquid held on the surface of a beam-intersecting sample probe. The impacting atoms deposit energy into the semivolatile matrix, causing desorption of ions, neutral molecules, and clusters of solvent and sample molecules. Desolvation follows desorption, and molecules (M) are usually ionised in a process of protonation to form M H. The mass spectra usually contain a large background of ions from the energy-moderating solvent (e.g., glycerol).