different supramolecular coordination polymers of [n,n'-di(pyrazin-2-yl)-pyridine-2,6-diamine]ni(ii) with anions and solvent molecules as a result of hydrogen bonding

Ni(II) complexes of N,N'–di(pyrazin–2–yl)pyridine–2,6–diamine (H2dpzpda) with different anions were synthesized and their structures were determined by X-ray diffraction. Hydrogen bonds between the amino groups and anions assembled the mononuclear molecules into different architectures. The perchlorate complex had a 1-D chain structure, whereas switching the anion from perchlorate to nitrate resulted in a corresponding change of the supramolecular structure from 1-D to 3-D. When the nitrate complex packed with the co-crystallized water, a double chain structure was formed through hydrogen bonding. The magnetic studies revealed values of g = 2.14 and D = 3.11 cm-1 for [Ni(H2dpzpda)2](ClO4)2 (1) and g = 2.18 and D = 2.19 cm-1 for [Ni(H2dpzpda)2](NO3)2 (2), respectively.