Dipole moment and conformation of CnH2n+1O(CH2CH2O)mH investigated by the measurements of permittivity and FT-IR spectra in heptane solutions and by ab initio calculations

The apparent dipole moments (mu) of 2-methoxyethanot (C1E1), 2-ethoxyethanol (C2E1), 2-(2-methoxyethoxy)ethanol (C1E2) and 2-(2-ethoxyethoxy)ethanol (C2E2) were determined in heptane solutions for the mole fraction range of 0 < x < 0.03 at T = 298.15 K. To calculate mu values the molar volumes for these solutions and the refractive indices of the pure components were determined at T = 298.15 K. FT-IR spectra for these solutions were also measured at T = 298 K. The conformations of these compounds and that of the dimer of C1E1 were predicted by ab initio calculations. In order to compare the calculated results with experimental, a statistical calculation was performed. The calculated conformers of the isolated molecules correlated well with the experimental results of the dipole moment and the IR spectra.