Sound propagation in liquid water: The puzzle continues

Sciortino, Francesco; Sastry, Srikanth
March 1994
Journal of Chemical Physics;3/1/1994, Vol. 100 Issue 5, p3881
Academic Journal
Experimental and simulation studies of sound propagation in water have observed, at large wave vectors k (k>=0.25 Å-1), a longitudinal sound mode with a velocity of about 3500 m/s, more than twice the hydrodynamic sound velocity. The relation between the hydrodynamic sound mode and the high frequency mode has been the center of contrasting interpretations. In this paper, we report extensive molecular dynamics simulations designed ad hoc to explore the intermediate and low k part of the collective spectrum. We calculate the dispersion relations for longitudinal and transverse collective modes from 0.026 to 1 Å-1 for a range of temperatures. At all temperatures studied, the sound velocity increases with k. At the highest studied temperature, the sound velocity changes from values comparable to hydrodynamic sound velocity to ones observed by neutron scattering experiments. We show that the viscoelastic approximation describes the data satisfactorily. We also perform normal mode analysis of quenched liquid configurations to obtain further information about the behavior observed at intermediate frequencies (50–100 cm-1). We find further positive dispersion of the sound branch at these frequencies and indications which suggest the interaction of the sound branch with localized modes as the origin of such dispersion.


Related Articles

  • Visualization of fast energy flow and solvent caging in unimolecular dynamics. Rejto, Paul A.; Bindewald, Eckart // Nature;5/11/1995, Vol. 375 Issue 6527, p129 

    Introduces an approach for analyzing energy flow in liquid-phase dynamics. Concept of work landscapes; Types of work landscapes; Results.

  • Two general methods for grand canonical ensemble simulation of molecules with internal flexibility. Chempath, Shaji; Clark, Louis A.; Snurr, Randall Q. // Journal of Chemical Physics;4/22/2003, Vol. 118 Issue 16, p7635 

    Two simulation methods are presented for generating a grand canonical ensemble of molecules with internal degrees of freedom. Molecular dynamics integration is used as a Monte Carlo perturbation move in these methods. The integration move helps to explore the intramolecular degrees of freedom...

  • Comment on "Molecular dynamics simulations in the grand canonical ensemble: Formulation of a bias potential for umbrella sampling" [J. Chem. Phys. 110, 8295 (1999)]. Mezei, Mihaly // Journal of Chemical Physics;1/8/2000, Vol. 112 Issue 2 

    The cavity-biased grand canonical ensemble Monte Carlo simulation method has been compared with a particular implementation of the grand canonical ensemble molecular dynamics method by examining the fluctuations during simulations of equivalent length. The Monte Carlo run exhibited an order of...

  • A method for accelerating the molecular dynamics simulation of infrequent events. Voter, Arthur F. // Journal of Chemical Physics;3/15/1997, Vol. 106 Issue 11, p4665 

    Describes a transition state theory (TST)-based method for accelerating and extending the molecular dyamics simulation of infrequent events. State to state evolution on the biased potential occurring in proper sequence; Exactness of long-time dynamical behavior if there are no TST-violating...

  • Phase equilibria in extended simple point charge ice-water systems. Báez, Luis A.; Clancy, Paulette // Journal of Chemical Physics;12/8/1995, Vol. 103 Issue 22, p9744 

    The characteristics of the solid/liquid transition for a modified Simple Point Charge model of water have been determined using free energy calculations supported by nonequilibrium Molecular Dynamics (NEMD) simulations. We have considered the behavior of liquid water and of a variety of ice...

  • Damascene process simulation using molecular dynamics. Ju, Shin-Pon; Weng, Cheng-I; Hwang, Chi-Chuan // Journal of Applied Physics;12/15/2002, Vol. 92 Issue 12, p7062 

    This article uses a molecular dynamics parallel computing technique to investigate trench filling in the damascene process. The qualitative behavior of the trench filling process for different incident energies and substrate temperatures is described in terms of the filling morphology and the...

  • A microscopic model for surface-induced diamond-to-graphite transitions. De Vita, Alessandro; Galli, Giulia // Nature;2/8/1996, Vol. 379 Issue 6565, p523 

    Presents the results of first-principles molecular dynamics simulations of a surface-induced diamond-to-graphite transition. Use of diamond thin films.

  • Molecular dynamics simulation of reactive ion etching of Si by energetic Cl ions. Hanson, D.E.; Voter, A.F.; Kress, J. D. // Journal of Applied Physics;10/1/1997, Vol. 82 Issue 7, p3552 

    Reports on the results from the molecular dynamics simulation of the etching of a Si surface by energetic Cl atoms. Energy dependence of the Si yield; Variation of Si yield with the impact angle of incidence; Stoichiometry of desorbed materials; Effect of a thermal background Cl flux to the...

  • Generalized Flory equations of state for copolymers modeled as square-well chain fluids. Gulati, Harpreet S.; Hall, Carol K. // Journal of Chemical Physics;5/1/1998, Vol. 108 Issue 17, p7478 

    Presents the formulation of Generalized Flory-Dimer (GFD) equations of state for copolymers modeled as heteronuclear chain fluids. Description of molecular model and simulation method for copolymer fluids study; Features of GFD theory; Application of GFD theory to square well copolymers;...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics