Magneto-structural maps and bridged-ligand effect for dichloro-bridged dinuclear copper(ii) complexes: a theoretical perspective.

Theoretical understanding of magneto-structural correlations in dichloro-bridged dicopper(ii) complexes can guide the design of magnetic materials having broad-scale applications. However, previous reports suggest these correlations are complicated and unclear. To clarify possible correlations, magnetic coupling constants ( J calc ) of variants of a representative {Cu-(μ-Cl) 2 -Cu} complex A were calculated through BS-DFT. The variation of the Cu-(μ-Cl)-Cu angle ( α ), Cu⋯Cu distance ( R 0 ), and Cu-Cl-Cu-Cl dihedral angle ( τ ) followed by structural optimization and calculation of the magnetic coupling constant ( J calc ) revealed several trends. J calc increased linearly with R 0 and τ , and initially increased and then decreased with α . Further, bridging ligand effects on J calc for dicopper(ii) complexes were evaluated through BS-DFT; the results revealed that J calc increased with increasing ligand field strength (I - < Br - < Cl - < N 3 - < F - ). Furthermore, a linear relationship was found between the spin density of the bridging ligand and J calc .