Reversible Guest-Induced Magnetic and Structural Single-Crystal-to-Single-Crystal Transformation in Microporous Coordination Network {[Ni(cyclam)]3[W(CN)8]2}n

Planar honeycomb-like coordination network {[Ni(cyclam)]3[W(CN)8]2}n (cyclam = 1,4,8,11-tetraazacyclotetradecane) was obtained in the self-assembly reaction of [Ni(cyclam)]2+ and [W(CN)]83-. Its structure is characterized by void channels along the a axis. The compound shows reversible water adsorption in the temperature range of 25-40 degrees C with the formation of {[Ni(cyclam)]3[W(CN)8]2}n.16nH2O, accompanied by single-crystal-to-single-crystal transformation. The structural transformation significantly changes the character of intraplane magnetic exchange interactions.