NMR study of monophthalocyaninatolanthanide (III) compounds

The variation of ~1H NMR shifts of monophthalocyaninatolanthanide(Ⅲ)compounds of nine rare earth elements from Sm~(3+)to Lu~(3+)(except Gd~(3+))was studied.It was found that a“triad effect”appears in the sign alteration of the induced chemical shifts of α,β protons in the phthalo- cyanine rings for the second half of the rare earth series,that is,~1H NMR spectra shift upfield for Tb~(3+),Dy~(3+)and Ho~(3+)compounds,while for Er~(3+),Tm~(3+)and Yb~(3+)the spectra shift downfield.The largest alteration of the chemical shifts appears in the compound with Tb~(3+).This is in agreement with the regularity obtained theoretically by Bleaney. The ~(13)C NMR spectra of several monophthalocyaninatolanthanide compounds have also been recorded.The variation of the chemical shifts was discussed.