title: Molecular Driving Forces behind the Tetrahydrofuran-Water Miscibility Gap.
abstract: The tetrahydrofuran-water binary system exhibits an unusual closed-loop miscibility gap (transitions from a miscible regime to an immiscible regime back to another miscible regime as the temperature increases). Here, using all-atom molecular dynamics simulations, we probe the structural and dynamical behavior of the binary system in the temperature regime of this gap at four different mass ratios, and we compare the behavior of bulk water and tetrahydrofuran. The changes in structure and dynamics observed in the simulations indicate that the temperature region associated with the miscibility gap is distinctive. Within the miscibility-gap temperature region, the self-diffusion of water is significantly altered and the second virial coefficients (pair-interaction strengths) show parabolic-like behavior. Overall, the results suggest that the gap is the result of differing trends with temperature of minor structural changes, which produces interaction virials with parabolic temperature dependence near the miscibility gap.
authors.affiliation: Center for Molecular Biophysics, University of Tennessee and Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States.|Department of Biochemistry and Cellular Molecular Biology, University of Tennessee , M407 Walters Life Sciences, 1414 Cumberland Avenue, Knoxville, Tennessee 37996, United States.
authors.forename: Micholas Dean
authors.initials: MD
authors.lastname: Smith
authors.affiliation: Center for Molecular Biophysics, University of Tennessee and Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States.|Joint Institute for Biological Sciences, University of Tennessee and Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States.
authors.forename: Barmak
authors.initials: B
authors.lastname: Mostofian
authors.affiliation: Center for Molecular Biophysics, University of Tennessee and Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States.
authors.forename: Loukas
authors.initials: L
authors.lastname: Petridis
authors.affiliation: Center for Molecular Biophysics, University of Tennessee and Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Cheng
authors.affiliation: Center for Molecular Biophysics, University of Tennessee and Oak Ridge National Laboratory , Oak Ridge, Tennessee 37830, United States.|Department of Biochemistry and Cellular Molecular Biology, University of Tennessee , M407 Walters Life Sciences, 1414 Cumberland Avenue, Knoxville, Tennessee 37996, United States.
authors.forename: Jeremy C
authors.initials: JC
authors.lastname: Smith