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The [M0O(bdt)~]-/[MoO(bdt)~]2-(H2bdt = benzene-I ,2-dithiol) redox couple, in dimethylformamide solution, is a fully reversible process at €+ = -350 mV vs. standard calomel electrode and each of these anions has been characterised by X-ray crystallo raphy; the metal-ligand bond lengths of the former are slightly shorter than those of the latter, MoV-0 = 1.668(3) 1, MolV-0 = 1.699(6) A, mean MoV-S = 2.377(1) A, MolV-S = 2.388(2) A.

Fly agaric accumulate vanadium in the form of amavadin, whose structure has been elucidated (see picture for the crystal structure). Amavadin contains one VIV center coordinated to two (S,S)‐hidpa3− ligands (H3hidpa=2,2′‐(hydroxyimino)dipropionic acid) through one η2‐NO− group and two unidentate carboxylato groups from each ligand. The arrangement of the two η2‐NO− groups leads to a chiral vanadium center, which has been characterized in both the Λ and Δ forms. The carboxylato groups of the amavadin anions bind cations, for example, Ca2+ ions, and/or become involved in hydrogen bonding.

A new N,O-bidentate pro-ligand (HL), [ML2] (M = Cu, Zn) and [CuL2][BF4] have been synthesised; [CuL2].4DMF and [CuL2][BF4].2CH2Cl2 have been crystallographically and spectroscopically characterised; these data indicate that [CuL2]+ cations are constituted as [Cu2+(L.)(L-)]+ and involve the phenoxyl radical L..