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Updated: Jan 19, 2026

Thermochemical Studies of NiII and ZnII Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Direct experimental evaluation of ligand-induced backbonding in nickel metallacyclic complexes
1The University of British Columbia, Department of Chemistry, 2036 Main Mall, Vancouver, British Columbia, Canada. pierre@chem.ubc.ca.
Abstract:
The details of ligand-induced backbonding in nickel diphosphine π complexes are explored using nickel L-edge (3d←2p) X-ray absorption spectroscopy as a means of quantifying the degree of backbonding derived from direct Ni 3d donation into the π ligand. It is observed that backbonding into weakly π acidic ligands such as alkenes and arenes is dominated by contributions from the diphosphine ligand via σ-donation, leading to activated metallacycles with a Ni(0) d10 metal centre. With more strongly π acidic ligands, however, metal contributions to backbonding increase substantially leading to a more electron-deficient metal centre that is best described as having a Ni(i) spectroscopic oxidation state.
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