DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Dynamics of molecular associates in methanol/water mixtures

Journal Article · · Physical Chemistry Chemical Physics. PCCP
DOI: https://doi.org/10.1039/d1cp04726d · OSTI ID:1978762

The dynamics of molecular associates in a methanol/water mixture was investigated using quasielastic neutron scattering. By measuring the signal from four methanol/water samples differing only by their isotopic composition, the relative motion of the water to methanol molecules, i.e. their mutual dynamics, was determined at the nanoscale. The thus obtained nanoscopic mutual diffusion coefficient signals a significantly slower process than the single particle diffusion of either methanol or water in the system as well as their macroscopic mutual diffusion. The data do not provide any indication of microsegregation in this preeminent alcohol/water mixture; however, they do indicate the existence of long lived but dynamic molecular associates of water and methanol molecules. Our analysis of the structural relaxation shows that the lifetime of molecular association through hydrogen bonding determines the fact that viscosity of the mixtures at intermediate concentrations is higher than that of both pure components.

Research Organization:
University of Illinois at Urbana-Champaign, IL (United States)
Sponsoring Organization:
National Institute of Standards and Technology (NIST); National Science Foundation (NSF); USDOE; USDOE Office of Science (SC)
Grant/Contract Number:
SC0014084
OSTI ID:
1978762
Journal Information:
Physical Chemistry Chemical Physics. PCCP, Journal Name: Physical Chemistry Chemical Physics. PCCP Journal Issue: 4 Vol. 24; ISSN 1463-9076
Publisher:
Royal Society of ChemistryCopyright Statement
Country of Publication:
United States
Language:
English

References (71)

LINCS: A linear constraint solver for molecular simulations journal September 1997
Settle: An analytical version of the SHAKE and RATTLE algorithm for rigid water models journal October 1992
Absolute measurements of the thermal conductivity of mixtures of alcohols with water journal July 1989
GROMACS: A message-passing parallel molecular dynamics implementation journal September 1995
The Disk Chopper Spectrometer at NIST: a new instrument for quasielastic neutron scattering studies journal August 2003
Using polarization analysis to separate the coherent and incoherent scattering from protein samples journal January 2010
LiquidLib: A comprehensive toolbox for analyzing classical and ab initio molecular dynamics simulations of liquids and liquid-like matter with applications to neutron scattering experiments journal July 2018
Molecular dynamics simulations of aqueous solutions of short chain alcohols. Excess properties and the temperature of maximum density journal January 2021
Hydrogen bonding in ethanol–water and trifluoroethanol–water mixtures studied by NMR and molecular dynamics simulation journal May 2016
Glycerol Hydrogen-Bonding Network Dominates Structure and Collective Dynamics in a Deep Eutectic Solvent journal January 2018
Collective Mesoscale Dynamics of Liquid 1-Dodecanol Studied by Neutron Spin-Echo Spectroscopy with Isotopic Substitution and Molecular Dynamics Simulation journal December 2018
Influence of Kosmotrope and Chaotrope Salts on Water Structural Relaxation journal October 2020
The Nanostructure of Water-in-Salt Electrolytes Revisited: Effect of the Anion Size journal July 2021
Liquid Structure with Nano-Heterogeneity Promotes Cationic Transport in Concentrated Electrolytes journal October 2017
Diffusion coefficients of methanol and water and the mutual diffusion coefficient in methanol-water solutions at 278 and 298 K journal November 1985
Prediction of velocity cross-correlation coefficients of binary liquid mixtures journal March 1989
The OPLS [optimized potentials for liquid simulations] potential functions for proteins, energy minimizations for crystals of cyclic peptides and crambin journal March 1988
Specific Heat Capacity at Constant Volume for Water, Methanol, and Their Mixtures at Temperatures from 300 K to 400 K and Pressures to 20 MPa journal July 2001
Excess isobaric heat capacities of water-n-alcohol mixtures journal October 1982
Isochoric Heat Capacities of Alkanols and Their Aqueous Mixtures journal October 2003
Densities and Viscosities of Methanol-Water Mixtures. journal October 1961
Temperature Dependence of the Volumetric Properties of Binary and Ternary Mixtures of Water (1) + Methanol (2) + Ethanol (3) at Ambient Pressure (81.5 kPa) journal September 2007
Solution Dynamics in Aqueous Monohydric Alcohol Systems journal May 2003
Nanoscale Segregation in Room Temperature Ionic Liquids journal May 2007
Hydrophobic Segregation, Phase Transitions and the Anomalous Thermodynamics of Water/Methanol Mixtures journal November 2012
Clustering Dynamics in Water/Methanol Mixtures: A Nuclear Magnetic Resonance Study at 205 K < T < 295 K journal August 2008
Dynamical Crossover and Breakdown of the Stokes−Einstein Relation in Confined Water and in Methanol-Diluted Bulk Water journal February 2010
Molecular segregation observed in a concentrated alcohol–water solution journal April 2002
Nanostructuration of ionic liquids: impact on the cation mobility. A multi-scale study journal January 2017
Relevance of hydrogen bonded associates to the transport properties and nanoscale dynamics of liquid and supercooled 2-propanol journal January 2021
Small-angle neutron scattering study of D 2 O–alcohol solutions journal January 1990
The structural properties of alcohol–water mixtures journal January 1966
Novel solvent properties of choline chloride/urea mixturesElectronic supplementary information (ESI) available: spectroscopic data. See http://www.rsc.org/suppdata/cc/b2/b210714g/ journal November 2002
Mesoscale inhomogeneities in aqueous solutions of small amphiphilic molecules journal January 2013
Fluctuations and micro-heterogeneity in mixtures of complex liquids journal January 2013
Solute interactions in dilute aqueous solutions. Part 1.—Microcalorimetric study of the hydrophobic interaction
  • Franks, Felix; Pedley, Michael; Reid, David S.
  • Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, Vol. 72, Issue 0 https://doi.org/10.1039/f19767200359
journal January 1976
Solute interactions in dilute solutions. Part 2.—A statistical mechanical study of the hydrophobic interaction
  • Clark, Alan H.; Franks, Felix; Pedley, Michael D.
  • Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, Vol. 73, Issue 0 https://doi.org/10.1039/f19777300290
journal January 1977
Segregation in aqueous methanol enhanced by cooling and compression journal May 2005
Kirkwood-Buff integrals of aqueous alcohol binary mixtures journal March 2006
Coherent dynamics of meta -toluidine investigated by quasielastic neutron scattering journal March 2012
Interpretation of the unusual behavior of H 2 O and D 2 O at low temperatures: Tests of a percolation model journal October 1980
Comparison of simple potential functions for simulating liquid water journal July 1983
A unified formulation of the constant temperature molecular dynamics methods journal July 1984
Molecular dynamics with coupling to an external bath journal October 1984
A smooth particle mesh Ewald method journal November 1995
A molecular dynamics study of the equation of state and the structure of supercooled aqueous solutions of methanol journal November 2012
Alcohol-induced drying of carbon nanotubes and its implications for alcohol/water separation: A molecular dynamics study journal May 2013
Low-temperature water dynamics in an aqueous methanol solution journal July 2013
Dynamical properties of water-methanol solutions journal February 2016
Dynamic signature of molecular association in methanol journal July 2016
The microscopic structure of cold aqueous methanol mixtures journal October 2016
Viscoelastic relaxations of high alcohols and alkanes: Effects of heterogeneous structure and translation-orientation coupling journal March 2017
Nanoscopic length scale dependence of hydrogen bonded molecular associates’ dynamics in methanol journal May 2017
Analysis of shear viscosity and viscoelastic relaxation of liquid methanol based on molecular dynamics simulation and mode-coupling theory journal June 2017
The Stokes-Einstein relation in water/methanol solutions journal June 2019
A molecular dynamics method for simulations in the canonical ensemble journal June 1984
Dynamical structure factors for a fluid binary mixture in the hydrodynamic limit journal January 1974
Viscosities of Binary and Ternary Mixtures of Water, Alcohol, Acetone, and Hexane journal October 2008
Structure of Binary Liquid Mixtures. I journal April 1967
Canonical dynamics: Equilibrium phase-space distributions journal March 1985
Structural Aspects of the Electrical Resistivity of Binary Alloys journal October 1970
Mutual diffusion in binary Ar-Kr mixtures and empirical diffusion models journal February 1996
Dynamical properties of water-methanol solutions studied by depolarized Rayleigh scattering journal August 1996
Microstructure of neat alcohols journal June 2007
Hydration of methanol in aqueous solution journal December 1993
Molecular Structure of Alcohol-Water Mixtures journal October 2003
Coherent structural relaxation of water from meso- to intermolecular scales measured using neutron spectroscopy with polarization analysis journal April 2020
Reduction and analysis of SANS and USANS data using IGOR Pro journal November 2006
The 30 m Small-Angle Neutron Scattering Instruments at the National Institute of Standards and Technology journal June 1998
Concentration fluctuations in water–methanol mixtures as studied by ultrasonic absorption journal February 1976
DAVE: A Comprehensive Software Suite for the Reduction, Visualization, and Analysis of Low Energy Neutron Spectroscopic Data
  • Azuah, Richard Tumanjong; Kneller, Larry R.; Qiu, Yiming
  • Journal of Research of the National Institute of Standards and Technology, Vol. 114, Issue 6 https://doi.org/10.6028/jres.114.025
journal November 2009