Vibrational Spectroscopic Study of [1,2-bis(4-pyridyl)ethane]metal(II) Tetracyanonickelate(II). 2 m-Xylene Clathrates

Four new Hofmann-type clathrates of the form M(bpa)2Ni(CN)4· 2m-xylene (M = Mn , Fe , Co and Ni; bpa = 1,2-bis(4-pyridyl)ethane) have been synthesized and characterized by vibrational spectroscopy. The M(bpa)2Ni(CN)4 (M = Fe and Co) host structure is similar to the classical Hofmann-type host framework composed of layers of a two dimensional catena-metal tetra-μ-cyanonickelate(II) network, but in M(bpa)2Ni(CN)4 (M = Mn and Ni), the Ni(CN)4 moiety behaves as a bidentate –[NC-Ni(CN)2-CN–]– unit in the host framework.