Calculation of Exchange Coupling Constants in Triply-Bridged Dinuclear Cu(II) Compounds Based on Spin-Flip Constricted Variational Density Functional Theory

The performance of the second-order spin-flip constricted variational density functional theory (SF-CV(2)-DFT) for the calculation of the exchange coupling constant (<i>J</i>) is assessed by application to a series of triply bridged Cu­(II) dinuclear complexes. A comparison of the <i>J</i> values based on SF-CV(2)-DFT with those obtained by the broken symmetry (BS) DFT method and experiment is provided. It is demonstrated that our methodology constitutes a viable alternative to the BS-DFT method. The strong dependence of the calculated exchange coupling constants on the applied functionals is demonstrated. Both SF-CV(2)-DFT and BS-DFT affords the best agreement with experiment for hybrid functionals.