Large zero-field splittings of the ground spin state arising from antisymmetric exchange effects in heterometallic triangles

Abstract

[Ru2Mn(O)(O2CtBu)6(py)3] has an S=5/2 ground state with a very large zero-field splitting (ZFS) of D=2.9 cm(-1), as characterized by EPR spectroscopy at 4-330 GHz. This is far too large to be due to the Mn(II) ion (D <0.2 cm(-1)), as shown from the {Fe2Mn} analogue, but can be modeled by antisymmetric exchange effects.

Keywords: EPR spectroscopy; antisymmetric exchange; electronic structure; exchange coupling; zero-field splitting.