Mass spectral studies of lanthanide chelates. I. Samarium, europium, gadolinium and terbium chelates of thenoyltrifluoroacetone

Abstract

The mass spectra of the lanthanide chelates of thenoyltrifluoroacetone, viz. Met{CF₃COCH=C(O-)-C₄H₃S}₃ (Met = Sm, Eu, Gd, Tb), have been obtained. All four spectra display similar fragmentation patterns. Fluorine migration to the metal with the concomitant loss of :CF₂ occurs with all four lanthanide chelates. Peaks were observed for the ions [MetF₂]⁺ (Met = Sm, Gd, Tb) and [MetF]⁺ (Met = Sm, Eu). The occurrence of [MetF]⁺ in the spectra of the samarium and europium chelates is in keeping with the tendency of these two lanthanides to be reduced to the bivalent state. On the other hand, oxidation of terbium(III) to terbium(IV) was not observed in the mass spectra.