Infrared spectroscopic study of Hofmann-Td-type clathrates (Ni(1,9-diaminononane)M(CN)4.2G;(M=Cd veya Hg:G=benzene, 1,2-dichlorobenzene, 1,4-dichlorobenzen)

INFRARED SPECTROSCOPIC STUDY OF HOFMANN-Td-TYPE CLATHRATES Ni(l,9-diaminononane)M(CN)4.2G; (M = Cd or Hg; G = benzene, 1,2-dichlorobenzene, 1,4-dichlorobenzen) Cemal PARLAK Physics Department, M. S. Thesis, 2004 Thesis Supervisors: Asist. Prof. Zeki KARTAL SUMMARY In this study Hofmann-Td-type clathrates, formulated as Ni(l,9-diaminononane)M(CN)4.2G (M = Cd or Hg; G = benzene, 1,2-dichlorobenzene, 1,4-dichlorobenzen), are obtained chemically for the first time. Infrared spectra of the clathrates are recorded with FTIR spectrometer in the spectroscopic region of the (4000 - 400) cm"1. The number of the guest molecules enter the structure are also determined by elemental analysis of clathrates. The assignments are performed for the ligand molecule, the M(CN)4 groups and the guest molecules separately. The vibrational frequencies of the clathrates are compared with frequencies of free 1,9-diaminononane molecule. It was observed that some of these vibrational frequencies are shifted in 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 M(CN)4"2 anions and Ni(l,9-diaminononane) cations in the host structures of the clathrates forms a three dimensional polymeric structure. In this structure the Cd or Hg atoms are surrounded in the tetrahedral form by four C atoms of cyanide anions. Ni atoms are surrounded also octahedrally by four N atoms of cyanide anions and two N atoms of ligand molecule in the trans form. 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 M(CN)4 groups are bounded the each other by Ni(l,9-diaminononane) in the there dimensional lattice form. In the host structure formed there are two different cavities namely a and p. The two guest molecules accommodates also in these cavities. Key Words: 1,9-diaminononane, 1,2-dichlorobenzene, 1,4-dichlorobenzene, Benzene, Hofmann-Td-type Clathrates, Infrared Spectroscopy.