An unprecedented octadecanuclear copper(II) pyrazolate-phosphonate nanocage: synthetic, structural, magnetic, and mechanistic study.

A novel octadecanuclear copper pyrazolate-phosphonate nanocage with a bowl-shaped arrangement of the copper(II) centers in the asymmetric unit is reported. Characterization of intermediates in both solid and solution states aids to propose the mechanism of such a giant aggregation. Magnetic studies affirm the presence of antiferromagnetic interactions between the adjacent copper(II) centers. Extensive supramolecular interactions result in a framework structure.