LIGATED LANTHANIDE CLUSTERS IN THE FAST-ATOM-BOMBARDMENT OF LANTHANIDE CARBOXYLATES

The fast atom bombardment (FAB) of acetates and malonates of lanthanides (Ln) reveals clustering as a result of ion - molecule reactions to give in the general case the ion [(LnO)(x)(RCO(2))(y)O-z](+) with x reaching 4, y reaching 3 and z reaching 4. Binary clusters [(LnO)(x)O-y](+) are also found, with x reaching high values. Ligand fragmentation occurs both in these series and also with complexes of Ln with glycine and mono- and trichloroacetate ions. Certain combinations of x, y and tare associated with markedly high levels of stability, e.g. in[(PrO)(2)(CH3CO2)O](+), [(PrO)(4)(CH3CO2)O-2](+), [(TbO)(4)(CH3CO2)](+), [HO(CH3CO2)](+) and [(LaO)(malonate)O-4](+)