Effect of External Electric Field upon Lower Alkanols

Abstract

Applying the Monte Carlo method, molecules of methanol, ethanol and 1-butanol are brought to temperature of 300 K and under the influence of external electric field of 0.01 a.u their electronic spectra are simulated with HyperChem 8.0 involving ZINDO/S semiempirical method. Particular molecules differently react to the electric field applied as shown by the electronic spectra simulated in the range of 250-2.84 nm. Total energy of the methanol and ethanol molecules turn slightly more negative in the electric field whereas that energy found for 1-butanol more significantly turn to less negative. HyperChem 8.0 software is used together with the AM1 method for optimization of the conformation of the molecules of methanol, ethanol, 1-propanol and 1-butanol. Then polarizability, charge distribution, potential and dipole moment for molecules placed in the external electric field of 0.000, 0.001, 0.01 and 0.05 a.u. are calculated. External field induces a slightly field strength dependent polarizability of the molecules and the electron density redistribution at particular atoms. Total dipole moment (DM) for particular alkanols increases with the strength of the field applied. There is particularly sharp increase in DM at 0.05 a.u. field. Key words: Butanol; Computer simulations; Ethanol; Methanol; Propanol