A study of molecular structure and vibrational spectra of copper(II) halide complex of 2-(2′-thienyl)pyridine

In this study, the metal(II) halide of 2-(2′-thienyl)pyridine, (C9H7NS), (with synonym, 2-(2′-pyridyl)thiophene and 2-thiophen-2-ylpyridine), (in abbreviated pyth) have been formed by the reaction with copper chloride and was formulated as [Cu(pyth)2Cl2]. The structure and vibrational wavenumbers of the formed compound have been calculated by using density functional theory (DFT/B3LYP) method with 6-31++G(d,p) and LANL2DZ basis sets in the ground state, for the first time. Comparison of the observed IR and micro-Raman fundamental frequencies of the mentioned compound and calculated results by density functional B3LYP/6-31++G(d,p) and B3LYP/LANL2DZ methods indicates that B3LYP/LANL2DZ is superior to the scaled B3LYP/6-31++G(d,p) approach for both molecular vibrational modes and optimized geometric parameters of [Cu(pyth)2Cl2] complex. The results of computations exhibit that the copper atom is surrounded by N atoms of pyth ligand molecule and Cl atoms.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The Cu(pyth)2Cl2 complex have been formed by the reaction with copper(II) chloride of 2-(2′-thienyl)pyridine. ► IR and micro-Raman spectral results of Cu(pyth)2Cl2 complex have been reported. ► The molecular structure, vibrational wavenumbers of Cu(pyth)2Cl2 complex have been calculated using DFT/B3LYP/6-31++G(d,p) level. ► The observed geometric parameters and vibrational frequencies have been compared with the computed results.