New isopolyoxovanadate ions identified by electrospray mass spectrometry

Ammonium metavanadate in aqueous solution at pH 4.5 displays in electrospra y mass spectrometry experiments the presence of the two series of anions [H xVyOz](-) (x=0, 1; y=1-9; z=3-23) and [HxVyOz](2-) (x=0, 1; y=3-17; z=9-44) as well as [H2VO4](-), [V10O28](6-) and [H5V10O28](-) ions. Further, the c ation series [Hm+1(VO3)(m)](+) (m=1-6), [Hm-1VmO3m-1](+) (m=4-10) and [Hm-3 VmO3m-1](+) (m=6-11) are observed. The series of protonated and unprotonate d anions differ by {V2O5} units, the formal building block in these cluster s. A range of polyoxovanadates not previously reported have been observed. (C) 1999 Elsevier Science S.A. All rights reserved.