Electronic versatility of vanadium in tris-chelates with redox-active ligands.

Spectroscopic and computational examination of the neutral tris-dioxolene complex [V(dbcat) 3 ] (dbcat 2- = 3,6-di- tert -butylcatecholate) reveals a Class III mixed-valent ground state. The radical is stabilised by delocalisation across the ligands mediated by the energy matched d orbital manifold of the V(V) centre. This electronic structure is compared to the tris-dithiolene and tris-diimine analogues that possess V(IV) and V(II) ions, respectively.