Spin frustration in the butterfly-like tetrameric [Ni4(µ-CO3)2(aetpy)8][ClO4]4 [aetpy = (2-aminoethyl)pyridine] complex. Structure and magnetic properties

Abstract

A new tetranuclear nickel compound, showing µ-CO₃ bridges and butterfly topology has been synthesised and structurally characterised. The complex [Ni₄(µ-CO₃)₂(aetpy)₈][ClO₄]₄, where aetpy corresponds to (2-aminoethyl)pyridine, crystallises in the tetragonal system, space group P4(2)2(1)2 (no. 94), a = 14.523(4), c = 16.566(5) Å and Z = 8. Magnetic measurements show an overall antiferromagnetic behaviour with a quasi-degenerate set of spin levels S = 0, S = 1 and S = 2 as a ground state, which may be rationalised in terms of a spin frustration system.