A homometallic ferrimagnet based on mixed antiferromagnetic and ferromagnetic interactions through oxamato and carboxylato bridges

Two novel coordination polymers (CPs), {Cu[Cu(L)(H₂O)-(py)] ₂}_n (1) and {Cu[Cu(L)(MeOH)]₂·2H ₂O}_n (2), were synthesized using 2-(oxaloamino)benzoic acid (H₃L) providing oxamate and carboxylate groups, and magnetically characterized. Different 2-D layer structures were formed based on oxamato-bridged tricopper units bridging via the carboxylate group. In compound 1, a simple antiferromagnetic interaction operates through the oxamato bridge in the tricopper core, whereas, 2 showed a tendency for ferrimagnetic ordering at 2 K, resulting from mixed antiferromagnetic and ferromagnetic interactions through oxamato and syn-anti-type carboxylato bridges.