Al Said, T.; Spinnato, D.; Holldack, K.; Neese, F.; Cornella, J.; Schnegg, A.: Direct Determination of a Giant Zero-Field Splitting of 5422 cm-1 in a Triplet Organobismuthinidene by Infrared Electron Paramagnetic Resonance. Journal of the American Chemical Society 147 (2025), p. 84–87
10.1021/jacs.4c14795
Open Access Version
Abstract:
Stable monocoordinated organobismuthinidenes were only recently isolated and analyzed toward their chemical and electronic structure. Quantum chemical calculations on tBu-MSFluind-Bi(I) (2) predicted an unusual electronic structure dominated by a triplet ground state and a spectacular zero-field splitting (ZFS) > 4500 cm–1. However, experimental evidence for these predictions remained elusive due to limitations in the available magnetic characterization techniques. Herein, we determine an axial ZFS of D = 5422 cm–1 for 2, by direct detection of triplet electron paramagnetic resonance using magneto-optical infrared spectroscopy. To date, this represents the largest ZFS experimentally measured.