The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Ilan Benjamin - One of the best experts on this subject based on the ideXlab platform.
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Hydronium Ion at the water/1,2-dichloroethane interface: Structure, thermodynamics, and dynamics of Ion transfer.
Journal of Chemical Physics, 2019Co-Authors: Ilan BenjaminAbstract:Molecular dynamics simulatIons including umbrella sampling free energy calculatIons are used to examine the structure, thermodynamics, and dynamics that accompany the transfer of the classical Hydronium Ion (H3O+) across the water/1,2-dichloroethane interface. The calculated free energy of transfer (17 ± 1 kcal/mol) is somewhat larger than the experimental value (14 kcal/mol). A detailed examinatIon of the hydratIon structure is provided, and several dynamical properties as a functIon of the distance along the interface normal are calculated. In particular, it is shown that the Hydronium Ion is transferred as an Eigen species, and while the three hydratIon shell water molecules’ average structure is conserved during the transfer, they may be exchanged with nearby water molecules with a rate that decreases as the Ion enters the organic phase.Molecular dynamics simulatIons including umbrella sampling free energy calculatIons are used to examine the structure, thermodynamics, and dynamics that accompany the transfer of the classical Hydronium Ion (H3O+) across the water/1,2-dichloroethane interface. The calculated free energy of transfer (17 ± 1 kcal/mol) is somewhat larger than the experimental value (14 kcal/mol). A detailed examinatIon of the hydratIon structure is provided, and several dynamical properties as a functIon of the distance along the interface normal are calculated. In particular, it is shown that the Hydronium Ion is transferred as an Eigen species, and while the three hydratIon shell water molecules’ average structure is conserved during the transfer, they may be exchanged with nearby water molecules with a rate that decreases as the Ion enters the organic phase.
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Hydronium Ion at the water 1 2 dichloroethane interface structure thermodynamics and dynamics of Ion transfer
Journal of Chemical Physics, 2019Co-Authors: Ilan BenjaminAbstract:Molecular dynamics simulatIons including umbrella sampling free energy calculatIons are used to examine the structure, thermodynamics, and dynamics that accompany the transfer of the classical Hydronium Ion (H3O+) across the water/1,2-dichloroethane interface. The calculated free energy of transfer (17 ± 1 kcal/mol) is somewhat larger than the experimental value (14 kcal/mol). A detailed examinatIon of the hydratIon structure is provided, and several dynamical properties as a functIon of the distance along the interface normal are calculated. In particular, it is shown that the Hydronium Ion is transferred as an Eigen species, and while the three hydratIon shell water molecules’ average structure is conserved during the transfer, they may be exchanged with nearby water molecules with a rate that decreases as the Ion enters the organic phase.Molecular dynamics simulatIons including umbrella sampling free energy calculatIons are used to examine the structure, thermodynamics, and dynamics that accompany the transfer of the classical Hydronium Ion (H3O+) across the water/1,2-dichloroethane interface. The calculated free energy of transfer (17 ± 1 kcal/mol) is somewhat larger than the experimental value (14 kcal/mol). A detailed examinatIon of the hydratIon structure is provided, and several dynamical properties as a functIon of the distance along the interface normal are calculated. In particular, it is shown that the Hydronium Ion is transferred as an Eigen species, and while the three hydratIon shell water molecules’ average structure is conserved during the transfer, they may be exchanged with nearby water molecules with a rate that decreases as the Ion enters the organic phase.
Liem X Dang - One of the best experts on this subject based on the ideXlab platform.
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SolvatIon of the Hydronium Ion at the water liquid/vapor interface
Journal of Chemical Physics, 2003Co-Authors: Liem X DangAbstract:In this study, we used constrained molecular dynamics techniques to investigate the transport of a Hydronium Ion across the water liquid/vapor interface. The computed transfer free energy was nearly unchanged as the Hydronium Ion approached the Gibbs dividing surface. The Ion crossed the interface with no substantial minimum free energy, and transport of the Hydronium Ion involved a change in the solvent compositIon of the solvatIon shells around the Ion.
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solvatIon of the Hydronium Ion at the water liquid vapor interface
Journal of Chemical Physics, 2003Co-Authors: Liem X DangAbstract:In this study, we used constrained molecular dynamics techniques to investigate the transport of a Hydronium Ion across the water liquid/vapor interface. The computed transfer free energy was nearly unchanged as the Hydronium Ion approached the Gibbs dividing surface. The Ion crossed the interface with no substantial minimum free energy, and transport of the Hydronium Ion involved a change in the solvent compositIon of the solvatIon shells around the Ion.
Patrick S. Nicholson - One of the best experts on this subject based on the ideXlab platform.
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The kinetics of ultrasonic/electrical-field assisted Hydronium Ion exchange of K+-β′′-Al2O3
Solid State Ionics, 1992Co-Authors: Narendra D Patel, Partho Sarkar, Patrick S. NicholsonAbstract:Abstract The rate of electrical-field-assisted, Hydronium-Ion-exchange of K + -β″-Al 2 O 3 ceramics was investigated. A model based on Ion migratIon from a decreasing source was proposed to interpret the kinetics of the exchange process. Results of the Ion exchange experiment with ultrasonic field superimpositIon plus a cycling dc field are also reported.
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the kinetics of ultrasonic electrical field assisted Hydronium Ion exchange of k β al2o3
Solid State Ionics, 1992Co-Authors: Narendra D Patel, Partho Sarkar, Patrick S. NicholsonAbstract:Abstract The rate of electrical-field-assisted, Hydronium-Ion-exchange of K + -β″-Al 2 O 3 ceramics was investigated. A model based on Ion migratIon from a decreasing source was proposed to interpret the kinetics of the exchange process. Results of the Ion exchange experiment with ultrasonic field superimpositIon plus a cycling dc field are also reported.
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Hydronium-Ion conductors based on β/β″-alumina and rare-earth silicates
Solid State Ionics, 1990Co-Authors: M. Zafar, Aaftab Munshi, Patrick S. Nicholson, Andrew StockmanAbstract:Abstract H 3 O + -β/β″-alumina and H 3 O + rare-earth silicates (HNRS where R = rare earth Ion) Hydronium-Ion conductors were prepared by Ion exchanging alkali-Ion precursors. Conductivity measurements show the HNRS to be superior Hydronium-Ion conductors but physically less stable. The Hydronium-Ion conductors investigated suffer reversible degradatIon between 120 and 400 °C.
M Catti - One of the best experts on this subject based on the ideXlab platform.
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neutron scattering study of the dynamics of Hydronium Ion in h3o zr2 po4 3 nasicon across the order disorder transitIon
Journal of Physical Chemistry B, 2004Co-Authors: L E Bove, M Catti, And A Paciaroni, F SacchettiAbstract:Neutron incoherent scattering measurements were performed on (H 3 O)Zr 2 (PO 4 ) 3 Nasicon by the quasi-elastic spectrometer IN13 (ILL, Grenoble), to characterize the slow proton dynamics of the H 3 O + Ion in this compound. Both quasi-elastic and elastic data were collected at temperatures above and below the order-disorder phase transitIon (T c = 177 K). Quasi-elastic contributIons with peak full widths at half-maximum of 12 and 33 μeV (corresponding to proton jumping times of 110 and 40 ps) were determined at 150 and 200 K, respectively. This supports a confined proton motIon both above (faster) and below (slower) the transitIon temperature, consistent with the full and partial disorder of the Hydronium Ion found in the high-T rhombohedral and low-T monoclinic phase, respectively, by previous neutron diffractIon experiments. Results of the elastic scans vs momentum transfer and temperature are analyzed and discussed.
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Neutron Scattering Study of the Dynamics of Hydronium Ion in (H3O)Zr2(PO4)3 Nasicon Across the Order−Disorder TransitIon
Journal of Physical Chemistry B, 2004Co-Authors: L E Bove, M Catti, And A Paciaroni, F SacchettiAbstract:Neutron incoherent scattering measurements were performed on (H 3 O)Zr 2 (PO 4 ) 3 Nasicon by the quasi-elastic spectrometer IN13 (ILL, Grenoble), to characterize the slow proton dynamics of the H 3 O + Ion in this compound. Both quasi-elastic and elastic data were collected at temperatures above and below the order-disorder phase transitIon (T c = 177 K). Quasi-elastic contributIons with peak full widths at half-maximum of 12 and 33 μeV (corresponding to proton jumping times of 110 and 40 ps) were determined at 150 and 200 K, respectively. This supports a confined proton motIon both above (faster) and below (slower) the transitIon temperature, consistent with the full and partial disorder of the Hydronium Ion found in the high-T rhombohedral and low-T monoclinic phase, respectively, by previous neutron diffractIon experiments. Results of the elastic scans vs momentum transfer and temperature are analyzed and discussed.
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order disorder of the Hydronium Ion and low temperature phase transitIon of h3o zr2 po4 3 nasicon by neutron diffractIon
Journal of Physical Chemistry B, 2002Co-Authors: M Catti, R M IbbersonAbstract:High-resolutIon powder neutron diffractIon data (HRPD, ISIS Facility, U.K.) were collected on (H 3 O)Zr 2 (PO 4 ) 3 between 4 and 300 K. In the range 175-180 K, a ferroelastic first-order phase transitIon from the rhombohedral R3c NASICON structure to a monoclinic distorted one was discovered. Rietveld structure refinements were performed at 300 K (a = 8.74848(3), c = 23.7598(1) A) and 4.5 K (space group C2/c or Cc, a = 15.0663(1), b = 8.7878(1), c = 9.3611(1) A, β = 122.498(1)°). At RT, the Hydronium Ion H 3 O + is pyramidal disordered over two inversIon-related configuratIons. At LT, H 3 O + becomes nearly planar, with two H atoms ordered and hydrogen-bonded to neighboring oxygens, and the third H atom disordered over two close positIons with 2/3 and 1/3 statistical occupancies. RelatIons with the structural features of Hydronium in other structures and the nature of order-disorder are discussed. An atomistic mechanism for proton conductivity is proposed.
Narendra D Patel - One of the best experts on this subject based on the ideXlab platform.
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the kinetics of ultrasonic electrical field assisted Hydronium Ion exchange of k β al2o3
Solid State Ionics, 1992Co-Authors: Narendra D Patel, Partho Sarkar, Patrick S. NicholsonAbstract:Abstract The rate of electrical-field-assisted, Hydronium-Ion-exchange of K + -β″-Al 2 O 3 ceramics was investigated. A model based on Ion migratIon from a decreasing source was proposed to interpret the kinetics of the exchange process. Results of the Ion exchange experiment with ultrasonic field superimpositIon plus a cycling dc field are also reported.
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The kinetics of ultrasonic/electrical-field assisted Hydronium Ion exchange of K+-β′′-Al2O3
Solid State Ionics, 1992Co-Authors: Narendra D Patel, Partho Sarkar, Patrick S. NicholsonAbstract:Abstract The rate of electrical-field-assisted, Hydronium-Ion-exchange of K + -β″-Al 2 O 3 ceramics was investigated. A model based on Ion migratIon from a decreasing source was proposed to interpret the kinetics of the exchange process. Results of the Ion exchange experiment with ultrasonic field superimpositIon plus a cycling dc field are also reported.
