Schiff bases are an important class of organic compounds. Schiff bases have biological activities such as antimicrobial, antifungal, antitumor activities and herbicidal properties. On the industrial scale, they have a wide range of applications, such as in dyes and pigments. Schiff base compounds display interesting photochromic and thermochromic features in the solid state and can be classified in terms of these properties. Schiff bases display two possible tautomeric forms, the enol-imine and the keto-amine forms. Depending on the tautomers, two types of intramolecular hydrogen bonds are observed in Schiff bases: O–H···N in enol-imine and N–H···O in keto-amine tautomers. The molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) 1H and 13C NMR chemical shift values of 2-{[(2-chlorophenyl)-imino]methyl}phenol in the ground state were calculated using the density functional method (B3LYP) with 6-31G(d) basis set. The calculated results show that the optimized geometry can well reproduce the crystal structure, and the theoretical vibrational frequencies and chemical shift values show good agreement with experimental values.

Keywords - DFT, FT-IR, NMR, Schiff Base

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