Infrared spectroscopic stud of Hofmann Td-type clathrates benzonitrile tetracyanocadmium, [Ni(benzonitrile)2Cd(CN)4.G]

In this study, Hofmann-Td-type clathrates, formulated as Ni(Benzonitrile)2Cd(CN)4.G (G = Benzene, 1,2-Dichlorobenzene, 1,3- Dichlorobenzene, 1,4- Dichlorobenzene, 1,4-Dioxane, Furan), have been obtained chemically for the first time. Infrared spectra of the clathrates is recorded with FTIR spectrometer in the spectroscopic region of the (4000 ? 200) cm?1. The assignment is performed for the ligand molecule, the Cd(CN)4 groups and the guest molecules separately. The vibrational frequencies of the clathrates are compared with frequencies of free benzonitrile molecule. It was observed that some of these vibrational frequencies are shifted with respect to the free molecule due to clathrates formation. The observed frequency shifts arise because of bounding metal, metal ligand vibrational modes and coupling.The Cd(CN)4-2 anions and Ni(Benzonitrile)2+2 cations in the host structures of the clathrates form a three dimensional polymeric structure. In this structure, Cd atom is surrounded in the tetrahedral form by four C atoms of cyanide anions. Ni atoms are also surrounded octahedrally by four N atoms of cyanide anions and two N atoms of ligand molecule. The ligand molecule is bound to Ni atom directly whereas four CN?s are bound to each other face to face in the CN groups. The Cd(CN)4 group is bounded the each other by Ni(Benzonitrile)2 in the there dimensional lattice form. In the host structure formed there are two different cavities namely ? and ß. The two guest molecules accommodates in these cavities, as well.Keywords: Benzene, 1,2- Dichlorobenzene, 1,3- Dichlorobenzene, 1,4- Dichlorobenzene, 1,4-Dioxane, Furan, Hofmann-Td-type Clathrates, Infrared Spectroscopy.