Isopolyoxorhenates observed by positive ion electrospray mass spectrometry

摘要

Unknown positive on isopolyoxorhenates have been observed using electrospray ionization mass spectrometry (ESI+). The ESI+ studies of ammonium and alkali metal (Na~+ and K~+) perrhenate salts in aqueous solution at pH 4.5 show the existence of the series [A_(x+1)Re_x~(VII)O_(4x)]~+ (where x = 1-5 and A = NH_4~+, Na~+ and K~+). In the potassiium perrhenate systme, the series [K_(x+)Re~VRe_x~(VII)O_(4x+3)]~+ (x = 0-4) has also been characterised. All of these four series have {AReO_4} as the aggregation unit. In the ammonium perrhenate system, the monomeric Re(VII)-containing species, [(NH_4)_2(H_2ReO_5)]~+, [(NH_4)_3(HReO_5)]~+ and [(NH_4)_4(ReO_5)]~+ were also detected.