Hydrogen bonding in supercritical water
نویسندگان
چکیده
We study the hydrogen bonding structure of water models at supercritical conditions by molecular dynamics to directly compare with recent microstructural data obtained by neutron diffraction with isotopic substitution (NDIS) experiments. We also study the angular dependence of the hydrogenoxygen pair distribution function to gain insight into the hydrogen bonding mechanism in the molecular models for water. The simulation results suggest that the angle-averaged radial distribution function go&-) measured by NDIS experiments may not provide a complete picture of the degree of hydrogen bonding.
منابع مشابه
Vacuum ultraviolet spectroscopy of the lowest-lying electronic state in subcritical and supercritical water
The nature and extent of hydrogen bonding in water has been scrutinized for decades, including how it manifests in optical properties. Here we report vacuum ultraviolet absorption spectra for the lowest-lying electronic state of subcritical and supercritical water. For subcritical water, the spectrum redshifts considerably with increasing temperature, demonstrating the gradual breakdown of the ...
متن کاملStructure, Dynamics, and Reactions of Supercritical Water Studied by NMR and Computer Simulation
The structure and properties of supercritical water is investigated in relation to the energy and environmental issues of the 21 century. Molecular interpretations are given to the temperature dependence of the hydrogen-bonding structure, dynamics, and chemical reactions of supercritical water. The three-dimensional network structure, characteristic of ambient water, is broken down in hot expan...
متن کاملProduction of Hydrogen and Synthesis gas via Cu-Ni/Al2O3 catalyzed gasification of bagasse in supercritical water media
Bagasse as a real biomass was converted to hydrogen rich gas via catalytic supercritical water gasification process. To find the effect of Cu on selectivity of products, Cu promoted Ni-γAl2O3 catalysts were prepared with 1 to 20wt% Ni and 0.5 to 10wt% Cu loadings via impregnation method. Catalysts were characterized by ICP, BET, XRD, H2 chemisorption and TEM technique as well CHNS analysis was ...
متن کاملEffect of the local hydrogen bonding network on the reorientational and translational dynamics in supercritical water.
Molecular dynamics simulations have been performed in a wide range of densities along a near critical isotherm of supercritical water in order to reveal the interconnection between the local hydrogen bonding (HB) network and several related dynamic properties. The results obtained have revealed a significant slowing down of reorientational dynamics of the water molecules as the value of the num...
متن کاملSolvation shell dynamics studied by molecular dynamics simulation in relation to the translational and rotational dynamics of supercritical water and benzene.
The solvation shell dynamics of supercritical water is analyzed by molecular dynamics simulation with emphasis on its relationship to the translational and rotational dynamics. The relaxation times of the solvation number (tau S), the velocity autocorrelation function (tau D), the angular momentum correlation function (tau J), and the second-order reorientational correlation function (tau 2R) a...
متن کامل