Reversible crystal-to-amorphous structural transformations and magnetic variations in single end-on azide-bridged M II (M = Mn, Ni) coordination polymers.

M-II (M = Mn, Ni) coordination frameworks, singly linked by end-on azide ligands, were prepared by employing the long, flexible spacer ligand, p-XBP4. These two-dimensional layer structures underwent reversible crystal-to-amorphous phase transformations during the hydration-dehydration process. Moreover, the magnetic nature changes from antiferromagnetic to ferromagnetic coupling when moving from Mn to Ni.