Formation of Negative Ions Under Inverted Field Ionization Conditions

Negative organic ions including those of thymine, perylene, and trinitrotoluene have been produced by subjecting the parent substances on a metal surface to the influence of a high positive electrostatic field. The field produced at highly curved metallic surfaces (below the threshold of field emission) may allow electron uptake by substances that have a sufficient electron affinity. The scope and implications of this novel mass spectrometric technique are discussed.