Six-coordinated Cd(II) centres as four- or six-connected nodes in coordination polymer networks containing bis(4-pyridyl)amine

The networks for 2 and 3 were 4-fold interpenetrated and isotopological. The reaction of CdSO4 with bpaH⁺ led to the formation of a two-dimensional (2D) hydrogen-bonded net (4). Complex 4 consisted of discrete six-coordinate mononuclear units linked into a 2D network by a number of different hydrogen-bonding interactions. The topological analysis of this network showed it to be reminiscent of a 2D diagonal section of an α-polonium network.