Journal article

Understanding the Origin of One- or Two-Step Valence Tautomeric Transitions in Bis(dioxolene)-Bridged Dinuclear Cobalt Complexes

Gemma K Gransbury, Brooke N Livesay, Jett T Janetzki, Moya A Hay, Robert W Gable, Matthew P Shores, Alyona Starikova, Colette Boskovic



Valence tautomerism (VT) involves a reversible stimulated intramolecular electron transfer between a redox-active ligand and redox-active metal. Bis(dioxolene)-bridged dinuclear cobalt compounds provide an avenue toward controlled two-step VT interconversions of the form {CoIII-cat-cat-CoIII} ⇌ {CoIII-cat-SQ-CoII}⇌{CoII-SQ-SQ-CoII} (cat2- = catecholate, SQ•- = semiquinonate). Design flexibility for dinuclear VT complexes confers an advantage over two-step spin crossover complexes for future applications in devices or materials. The four dinuclear cobalt complexes in this study are bridged by deprotonated 3,3,3',3'-tetramethyl-1,1'-spirobi(indan)-5,5',6,6'-tetraol (spiroH4) or 3,3,3',3'-tetra..

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Awarded by Australian Research Council

Awarded by Russian Science Foundation

Awarded by US National Science Foundation

Funding Acknowledgements

C.B. thanks the Australian Research Council for financial support (DP150100353 and DP190100854). G.K.G. acknowledges the support of an Elizabeth and Vernon Puzey Scholarship from the University of Melbourne, an Australian Government Research Training Award and a Postgraduate Student Travel Bursary from the Royal Australian Chemical Institute. We thank Tina Tezgerevska for synthesis of the ligand (H<INF>3</INF>tpa)(ClO<INF>4</INF>)<INF>3</INF>, Dr Elodie Rousset for assistance with the synthesis of tpa, and Ken Gransbury for help conceptualizing figures. This research was undertaken in part using the MX1 and MX2 beamlines at the Australian Synchrotron, part of ANSTO, and made use of the ACRF detector. A.S. thanks the Russian Science Foundation for financial support (19-73-00090). M.P.S. and B.N.L. thank the US National Science Foundation for financial support (NSF-CHE-1800554).