Magnetic compensation in the bimetallic oxalates

Bimetallic oxalates are layered molecule-based magnets with either ferromagnetic or antiferromagnetic interactions between transition metals M(II) and M′ (III) on an open-honeycomb lattice. Some Fe(II)Fe(III) bimetallic oxalates exhibit magnetic compensation (MC) at a compensation temperature Tcomp ≈30 K below the ferrimagnetic transition temperature Tc≈45 K. To see if MC is possible in other bimetallic oxalates, we construct a theoretical model for bimetallic oxalates that exhibit antiferromagnetic interactions. By varying the M(II) and M′ (III) average orbital angular momentum, which can be controlled by the choice of interlayer cations, we find regions of MC in the families M(II)Mn(III) with M=Fe, Co, or Ni and V (II) M′ (III) with M′ =Cr or V but not in the family M(II)Ru(III) with M=Fe or Cu.