New Insights into the Structure of Glycols and Derivatives: A Comparative X-Ray Diffraction, Raman and Molecular Dynamics Study of Ethane-1,2-Diol, 2-Methoxyethan-1-ol and 1,2-Dimethoxy Ethane
In this study, we report a detailed experimental and theoretical investigation of three glycol
derivatives, namely ethane-1,2-diol, 2-methoxyethan-1-ol and 1,2-dimethoxy ethane. For the first
time, the X-ray spectra of the latter two liquids was measured at room temperature, and they were
compared with the newly measured spectrum of ethane-1,2-diol. The experimental diffraction patterns
were interpreted very satisfactorily with molecular dynamics calculations, and suggest that in liquid
ethane-1,2-diol most molecules are found in gauche conformation, with intramolecular hydrogen bonds
between the two hydroxyl groups. Intramolecular H-bonds are established in the mono-alkylated diol,
but the interaction is weaker. The EDXD study also evidences strong intermolecular hydrogen-bond
interactions, with short O···O correlations in both systems, while longer methyl-methyl interactions
are found in 1,2-dimethoxy ethane. X-ray studies are complemented by micro Raman investigations
at room temperature and at 80 ◦C, that confirm the conformational analysis predicted by X-ray
experiments and simulations.