biostudies-literatureMeng YSNational Natural Science Foundation of ChinaNatural Science Foundation of Jiangsu Province7156-7162https://www.ebi.ac.uk/biostudies/studies/S-EPMC5951210biostudies-literatureUnknown6(12)The slow magnetic relaxation typical for single-ion magnets has been known for certain low-coordinate 3d metal complexes with d⁶, d⁷, and d⁹ electronic configurations, but never for d⁸ complexes. Herein, we report a study on two-coordinate d⁸ cobalt(i)-N-heterocyclic carbene complexes, for which slow magnetic relaxation behavior was observed for [Co(IMes)₂][BPh₄] (IMes: 1,3-dimesitylimidazol-2-ylidene) under an applied dc field. The system represents the first d⁸ single-ion magnet, and features a fitted energy barrier of <i>U</i>_eff = 21.3 cm^-1 and pre-exponential factor of <i>τ</i>₀ = 6.6 × 10^-6 s. The analog two-coordinate cobalt(i) complexes with different Chemical scienceObservation of the single-ion magnet behavior of d⁸ ions on two-coordinate Co(i)-NHC complexes.PMC595121021222208, 21321001, 91422302, 21421091 and 2143200BK20151542Wang BWMo ZZhang YQDeng LGao SMeng YSfalseObservation of the single-ion magnet behavior of d⁸ ions on two-coordinate Co(i)-NHC complexes.The slow magnetic relaxation typical for single-ion magnets has been known for certain low-coordinate 3d metal complexes with d⁶, d⁷, and d⁹ electronic configurations, but never for d⁸ complexes. Herein, we report a study on two-coordinate d⁸ cobalt(i)-N-heterocyclic carbene complexes, for which slow magnetic relaxation behavior was observed for [Co(IMes)₂][BPh₄] (IMes: 1,3-dimesitylimidazol-2-ylidene) under an applied dc field. The system represents the first d⁸ single-ion magnet, and features a fitted energy barrier of <i>U</i>_eff = 21.3 cm^-1 and pre-exponential factor of <i>τ</i>₀ = 6.6 × 10^-6 s. The analog two-coordinate cobalt(i) complexes with different 2015-01-01T00:00:00Z2015 Dec2026-05-06T20:15:44.488Z2019-03-26T23:40:28ZS-EPMC59512102986195210.1039/c5sc02611c