Antiferromagnetic interactions in melamine-bridged trinuclear cobalt complex

The hydrothermal assembly of Co(OAc)2 · 4H2O with isophthalatic acid (H2ip) and melamine (ma) yielded a novel 3D coordination polymeric complex, {[Co3(ma)(ip)3] · 2H2O}n (1), which presents an unusual non-interpenetrated pseudo-primitive cubic (pcu) topology constructed from a 6-connected trinuclear Co(II) SBU. The study of magnetic properties indicates that antiferromagnetic coupling interactions exist both between the adjacent Co(II) sites and between the adjacent trimers. So the melamine molecule participates in transferring magnetic interactions for the first time.