Two-dimensional square grid of neutral phosphonate ligands and eight-coordinated metal ions

Two dimensional coordination polymer [CdL2(NO3)2]n (where L = 4,4′-bis(dimethylphosphonomethyl)biphenyl) has been achieved. The crystal structure and molecular composition are measured using elemental analysis and X-ray crystal structure. Two-dimensional square grid was formed by semi-rigid phosphonate ligands bridge metals, in which the metals adopt rare eight-coordinated geometry. Weak C–H⋯O hydrogen bonds which between coordinated nitrate anion and methyl group of phosphonate ligands link two dimensional grids generating three dimensional supramolecular networks without interpenetration.