GAS-PHASE MULTIPLY-CHARGED ANIONS

Singly charged negative ions in the gas phase have attracted considera ble experimental and theoretical attention over the past decades. Howe ver, the existence of free doubly or multiply charged negative ions, i n particular those of small systems, has remained a curiosity and a ma tter of some controversy, Recent experimental and quantum mechanical s tudies show that multiply charged negative ions of small molecules and clusters can exist as isolated entities.