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Title: Propane–Water Mixtures Confined within Cylindrical Silica Nanopores: Structural and Dynamical Properties Probed by Molecular Dynamics

Authors:
 [1]; ORCiD logo [1];  [2];  [2]
  1. Department of Chemical Engineering, University College London, London WC1E 6BT United Kingdom
  2. School of Earth Sciences, Ohio State University, Columbus, Ohio 43210 United States
Publication Date:
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1396636
Grant/Contract Number:
SC0006878
Resource Type:
Journal Article: Published Article
Journal Name:
Langmuir
Additional Journal Information:
Journal Volume: 33; Journal Issue: 42; Related Information: CHORUS Timestamp: 2017-11-06 16:05:45; Journal ID: ISSN 0743-7463
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English

Citation Formats

Le, Tran Thi Bao, Striolo, Alberto, Gautam, Siddharth S., and Cole, David R.. Propane–Water Mixtures Confined within Cylindrical Silica Nanopores: Structural and Dynamical Properties Probed by Molecular Dynamics. United States: N. p., 2017. Web. doi:10.1021/acs.langmuir.7b03093.
Le, Tran Thi Bao, Striolo, Alberto, Gautam, Siddharth S., & Cole, David R.. Propane–Water Mixtures Confined within Cylindrical Silica Nanopores: Structural and Dynamical Properties Probed by Molecular Dynamics. United States. doi:10.1021/acs.langmuir.7b03093.
Le, Tran Thi Bao, Striolo, Alberto, Gautam, Siddharth S., and Cole, David R.. 2017. "Propane–Water Mixtures Confined within Cylindrical Silica Nanopores: Structural and Dynamical Properties Probed by Molecular Dynamics". United States. doi:10.1021/acs.langmuir.7b03093.
@article{osti_1396636,
title = {Propane–Water Mixtures Confined within Cylindrical Silica Nanopores: Structural and Dynamical Properties Probed by Molecular Dynamics},
author = {Le, Tran Thi Bao and Striolo, Alberto and Gautam, Siddharth S. and Cole, David R.},
abstractNote = {},
doi = {10.1021/acs.langmuir.7b03093},
journal = {Langmuir},
number = 42,
volume = 33,
place = {United States},
year = 2017,
month = 9
}

Journal Article:
Free Publicly Available Full Text
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  • A dynamic nuclear magnetic resonance (NMR) study of the polar fluids ethanol (EtOH) and 2,2,2-trifluoroethanol (TFE) confined to porous silica sol-gel glasses is reported. The {sup 13}C NMR spin-lattice relaxation times, T{sub 1}, were measured in glasses with pore radii ranging from 18.9 to 54.8 A, over a temperature range from -13.6 to 30.5{degree}C. The data were analyzed in terms of the two-state, fast exchange model, and surface layer relaxation times, T{sub 1s}, were calculated. On the basis of surface enhancement factors, T{sub 1b}/T{sub 1s}, where T{sub 1b} is the relaxation time of the bulk liquid, it was concluded thatmore » the more acidic TFE has a weaker hydrogen bond interaction with silica, due to the fact that the alcohols serve as hydrogen bond acceptors. The experiment shows that EtOH and TFE have nearly identical surface layer viscosities, originating from the differences in hydrogen bonding with the silica surface. Confinement was found to have little effect on the internal rotation of terminal CF{sub 3} or CH{sub 3} groups. 32 refs., 2 figs., 3 tabs.« less
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  • An amorphous silicon structure is obtained with a computer simulation based on a new molecular-dynamics technique in which the interatomic potential is derived from a parameter-free quantum mechanical method. Our results for the atomic structure, the phonon spectrum, and the electronic properties are in excellent agreement with experiment. In addition we study details of the microscopic dynamics which are not directly accessible to experiment. We find in particular that structural defects are associated with weak bonds. These may give rise to low-frequency vibrational modes.