Vibrational Spectroscopic Investigation on Some M(Benzonitrile)2Ni(CN)4 Complexes (M = Ni, Zn, Cd, and Hg)

Abstract

The first synthesis of benzonitrile tetracyanonickelate complexes, represented by the general formula M(benzonitrile) 2 Ni(CN) 4 (M = Ni, Zn, Cd, and Hg), is reported. Fourier transform infrared spectroscopy and Raman spectroscopic data in the region of 4,000-400 cm −1 are presented, and the vibrational frequencies are assigned and explained in detail. The thermal behavior of these complexes was also investigated by thermogravimetric analysis, differential thermal analysis, and derivative thermal gravimetric analysis. The spectral and thermal analysis results of the newly synthesized complexes suggest that these complexes are new examples of Hofmann-type complexes. The spectral data obtained show that the complexes consist of |M-Ni(CN) 4 | ∞ polymeric layers with the ligand (benzonitrile) molecules bound to metal through the N-donor atom of the cyanide group.

Synthesis of Hofmann-type Zn(H2O)2Ni(CN)4.nG (G = water and 1,4-dioxane)clathrates and the determination of their structural properties by variousspectroscopic methods

“…This second step of the thermal analysis took place for crystal 2 at a temperature range of 100-119°C, with a These thermal decomposition results showed that crystals 1 and 2 were 2 new examples of Hofmann-type clathrates. Similar decomposition stages were observed for other Hofmann-type clathrates [5,33,[35][36][37][38][39].…”

“…The values of shifting to high frequencies in the IR and Raman spectra of the crystals were 18 and 21 cm −1 for crystal 1 and 21 and 27 cm −1 for crystal 2, respectively. Shifts to these high and low wavenumbers were also observed in studies conducted by other researchers with different ligand molecules [5][6][7].…”

“…Furthermore, frequencies of the C ≡N group vibrations in the compounds obtained depended on the electronegativity of the transition metal atom in that compound, its environment, and the number of bonds it formed with the oxidation state. The frequency values of the C ≡N vibrations in a chemical compound depend on the type of metal, electronegativity, chemical environment, oxidation state, and number of bonds it makes [5][6][7]24,25].…”

“…The various structural properties of Hofmann-type complexes and clathrates can be explained by various spectroscopic methods, such as vibrational (infrared (IR) and Raman), nuclear magnetic resonance, electron spin resonance, thermal analysis, single-crystal X-ray diffraction (SC-XRD) techniques, and magnetic moment spectroscopy. The formation of Hofmann-type complexes and clathrates and/or interactions of the guest molecule with the host structure can be easily understood by means of vibrational spectroscopy [5][6][7].…”

“…Broad and descriptive information about Hofmann-type compounds and clathrates can be found in various studies [1][2][3][4][5][6][7].…”