A three-dimensional mixed-ligand coordination polymer featuring strongly antiferromagnetically coupled dinuclear copper paddlewheels linked into a 6-connected self-penetrated network

The coordination polymer {[Cu-2(glu)(2)(bpmp)]center dot 4H(2)O}(n) (1, glu = glutarate, bpmp = N,N'-bis(4-pyridyl)piperazine) was prepared via solution-phase methods. Single-crystal X-ray diffraction revealed the presence of [Cu-2(glu)(2)](n) layers containing paddlewheel dinuclear units. These layers are connected by tethering bpmp ligands into a self-penetrated three-dimensional covalent network with 6-connected 4(4)6(10)8 topology. Variable-temperature magnetic studies indicated the presence of very strong anti ferromagnetic coupling (J = -283(8) cm(-1)) within the {Cu-2} dinuclear units of 1. Incipient channels within the self-penetrated framework are occupied by infinite C(4) water molecule chains.