Heteromolecular Structure Formation in Aqueous Solutions of Ethanol, Tetrahydrofuran and Dimethylformamide
The refractometric method has been used to determine optical properties of concentration features of aqueous solutions of ethanol, tetrahydrofuran and dimethylformamide at the room temperature. Changes in dielectric permittivity of aqueous solutions of ethanol, tetrahydrofuran and dimethylformamide in a wide range of concentrations (0÷1.0 molar fraction) have been studied using molecular dynamics method. The curves depending on the concentration of experimental data on excess refractive indices and excess dielectric permittivity were compared. It has been shown that stable heteromolecular complexes in binary solutions are formed in the concentration range of 0.3÷0.4 mole fractions. The real and complex part of dielectric permittivity was obtained from dipole-dipole autocorrelation functions of molecules. At the concentrations of C = 0.3 / 0.4 m.f. the heteromolecular structures with hydrogen bonds are formed. This is confirmed by the extremum values of excessive dielectric permittivity and excessive refractive index of aqueous solutions.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1130107Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 822
 Kaatze, U. Bound water: Evidence from and implications for the dielectric properties of aqueous solutions. Journal of Molecular Liquids. 2011, 162 (3), 105–112.
 Fukasawa, T.; Sato, T.; Watanabe, J.; Hama, Y.; Kunz, W.; Buchner, R. Relation between dielectric and low-frequency Raman spectra of hydrogen-bond liquids. Phys Rev Lett. 2005, 95 (19), 197802.
 Vrbka L., Jungwirth P., Molecular dynamics simulations of freezing of water and salt solutions, J. Mol. Liq. 2006, 134, 64–70
 Razzokov, D.; Ismailova, O. B.; Mamatkulov, Sh. I.; Trunilina, O. V.; Kokhkharov A. M. Heteromolecular structures in aqueous solutions of dimethylformamide and tetrahydrofuran, according to molecular dynamics data. Russian Journal of Physical Chemistry A. 2014, 88 (9), 1500–1506.
 Frisch M.J, Trucks G.W., et. al. Gaussian 03. ‒USA: Wallingford CT, 2009 (electronic ‒Powles J.G. Dielectric relaxation and the internal field. J. Chem. Phys. 1953, 21, 633-637.
 Hess B., Kutzner C., van der Spoel D., Lindahl E. GROMACS 4: Algorithms for Highly Efficient, Load-Balanced, and Scalable Molecular Simulation. J Chem Theory Comput. 2008, 4(3), 435-47.
 Saiz L., Padró J. A., Guàrdia E. Structure and Dynamics of Liquid Ethanol. J. Phys. Chem. B, 1997, 101 (1), 78–86.
 González M. A., Enciso E., Bermejo F. J., Bée M. Ethanol force fields: A molecular dynamics study of polarization effects on different phases. The Journal of Chemical Physics, 1999,110, 8045.
 Shirts M. R., Pande V. S. Solvation free energies of amino acid side chain analogs for common molecular mechanics water models. Journal of Chemical Physics. 2005, 122, 134508.
 Essmann U., Perera L., Berkowitz M., Darden T., Lee H., Pedersen L. A smooth particle mesh Ewald method. The Journal of chemical physics, 1995, 103 (19), 8577-8593.