Hydrogen bond lifetimes and statistics of aqueous mono‐, di‐ and tri‐ethylene glycol

Abstract

Hydrogen bond statistics, energy distributions of hydrogen bonds and hydrogen bond lifetimes for aqueous monoethylene glycol (MEG), diethylene glycol (DEG), and triethylene glycol (TEG) were investigated at temperatures ranging from 275 to 370 K at 101.325 kPa using molecular dynamics simulations. Each individual type of hydrogen bond were studied separately to better understand how each type of hydrogen bond affected the collective behavior often measured in experiments. We also studied the effects of glycols on water–water hydrogen bond structures and lifetimes. Decay constants for hydroxyl type hydrogen bonds, as well as for water based hydrogen bonds were in the same order, thus indicating that all these hydrogen bonds play an essential role in the process of dielectric relaxation. Correlations between water hydrogen bond distances and angles were not affected markedly by adding glycols. However, hydrogen bond lifetimes increased by 9, 29, and 62 times by adding MEG, DEG, and TEG, respectively. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1674–1689, 2017