The structure of a lanthanide porphyrin complex was reinvestigated using a new treatment for the paramagnetic NMR shifts. It was found to differ from that obtained previously in that the ion was closer to the macrocyclic ligand. The new treatment is based on ab inifio estimation of the coefficients describing the anisotropy of magnetic susceptibility, proportional to the pseudo-contact shifts. These coefficients were estimated using an electrostatic model of the complex; the 'extra' Egand @-diketonate) was taken into account and shown to be essential. The NMR spectrum of a non-axial complex under conditions of restricted rotation of the 'extra' Egand is described.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.