Two sandwich arsenomolybdates based on the new building block As(iii)Mo7O279−: [Cr2(AsMo7O27)2]12− and [Cu2(AsMo7O27)2]14−

Abstract

The polyanions [Cr₂(AsMo₇O₂₇)₂]¹²⁻ (1a) or [Cu₂(AsMo₇O₂₇)₂]¹⁴⁻ (2a) have sandwich-like structures wrapping two transition metals between two [As(III)Mo₇O₂₇]⁹⁻ fragments, and the fragment is unprecedented and can be viewed as a mono-capped hexavacant B-α-Keggin subunit with a central AsO₃group.