“…At higher pH levels (> 4.5), the dimeric and/or polymeric compound, {H 2 [VCl 2 (Ad Ϫ )O]} n , was isolated. 19 The stoichiometry, stability and modes of co-ordination have been studied, by spectroscopic methods, for vanadyl complexes of -asparagine and -glutamine. 20 The two series of octahedral oxovanadium() complexes containing the tetradentate amidate ligands Hcapca 1 and H 2 capcah 2, trans-[VOX(capca)] 0/ϩ (X = Cl, SCN, N 3 , OAc, PhCOO, Im, Bu n NH 2 ) and cis-[VOX(Hcapcah)] 0/ϩ (X = Cl, SCN,N 3 , Im), have been prepared and characterised, including by X-ray crystallographic and EPR techniques.…”