COMPUTATIONAL STUDY OF HYDROGEN BONDED COMPLEX OF ETHANOL AND WATER USING VARIOUS FUNCTIONALS ON THE BASIS OF DENSITY FUNCTIONAL THEORY

Abstract

Computational study of hydrogen bonded complex of ethanol and water using various functionals on the basis of density functional theory has been carried out using 6- 311++G(d,p), 6-311++G(2d,2p), and aug-cc-pVTZ basis sets. We have calculated binding energy, zero point vibrational energy, distance of the bond formed in the complex, bond angle after complex formation, frequency shift, electron density, and laplacian of electron density for the ethanol and water complex. The binding energy of the complex was found to be in the range of -4.258 kcal/mole to -6.232 kcal/mole . We have calculated the zero-point vibrational energy of the complex and found to be in the range of 1.54 kcal/mole to 1.85 kcal/mole . We have found the distance of bond formation in the complex in the range of 1.907 ˚A to 2.103 ˚A, the bond angle in the range of 172.73◦ to 178.80◦ , and frequency shift in the range of -151.76 cm−1 to -85.99 cm−1 . The electron density(ρ) and laplacian of electron density(∇2ρ) at bond critical points for the C2H5OH...H2O complexes are analyzed in DFT, and different levels of approximation by using AIM All software.