Cooper (II) Cubanes with (Cu4O4) core and well defined S=1 ground state

Abstract

The reaction of 2-pyridinemethanol with copper 4-fluorobenzoate has yielded a family of type II cubanes with formula [Cu4(pymO)4(4-F-PhCOO)3(NO3)] (1), [Cu4(pymO)4(4-F-PhCOO)4] (2) and [Cu4(pymO)4(4-F-PhCOO)4(H2O)] (3). These systems exhibit an unexpected S = 1 ground state and their magnetic properties have been unambiguously characterized and rationalized as a function of the asymmetry of the {Cu4O4} cage and Cu-O-Cu bond angles. Analysis of the coupling constants was performed applying new interaction schemes. Magneto-structural correlations have been performed from the analysis of previously reported type II copper cubanes.