Dynamic Properties Of Liquids Research Articles

An introduction to the properties of condensed matter

Glossary Preface 1. Condensed matter 2. Properties of elastic solids 3. Dynamics and stability of elastic media 4. Static properties of liquids 5. Dynamic properties of liquids 6. Diffusion Appendices Index.

Fluid flow formation resulting from forced vibration of a growing crystal

A characteristic type of convection in the liquid phase near a growing crystal subject to low frequency vibration has been identified. Results of the present investigation show that these vortex flows represent a new type of steady flow which is induced by vibration. The form, dimensions and intensity of the flow in connection with vibrational parameters and dynamic properties of liquid have been studied. The effects of vibrational convection on the heat and mass transfer in crystal growth by different techniques are analyzed. As an example, the results on the growth by the Czochralski technique of a sodium nitrate crystal subject to vibrations with amplitudes from 0.005 to 0.5 mm and frequencies up to 100 Hz are presented.

Molecular dynamics studies of Lennard-Jones liquid mixtures. VI. Temperature, density, and unlike interaction dependencies in static and dynamic properties of binary equimolar mixtures

Molecular dynamics calculations have been made for pure fluids and binary equimolar mixtures each containing 108 Lennard-Jones particles. The purpose of the calculations is threefold. First, the effect of the attractive term on the dynamic properties of liquids has been examined at fixed temperature and number density with equimolar mixtures of three models in which different combining rules for the energy parameter are assumed. Next the temperature and density dependences in static and dynamic properties of Lorentz–Berthelot mixture have been investigated. The variation of the velocity autocorrelation function with temperature and number density has been examined in detail. The activation energy for self-diffusion at constant number density is almost independent of the strength of interparticle interaction and is estimated to be 0.35 kcal mol−1, which is comparable with that for argon. In spite of remarkable change in the pattern of velocity autocorrelation function in the density range studied, self-diffusion coefficient changes linearly with density. Finally, a preliminary calculation on the microscopic process of mixing has been described.

?Thought-experiments? by molecular dynamics

A method for studying the dynamical properties of liquids by molecular dynamics simulation is described. Its basis is the measurement of the response to a weak applied field of appropriate character. The explicit form of the mechanical perturbation is worked out in several cases, and details are given of the numerical techniques used in implementing the method.

Millikan "Oil Drop" Stabilized by Growth

A diffusion cloud chamber has been used to qualitatively study some dynamic properties of liquid drops by suspending them in an electric field at the plane of saturation (p/ps = 1, where p is the actual partial pressure of the vapor at a given elevation and ps is the equilibrium pressure at that temperature characteristic of that elevation). By varying the strength of the electric field, it is possible to change the size of the suspended droplets and even, if desired, to isolate a single drop.

Molecular Dynamics Studies of Lennard‐Jones Liquid Mixtures. III. Structural and Thermodynamic Properties of Several Equimolar Mixtures

AbstractMolecular dynamics calculations have been made for three equimolar mixtures of Lennard‐Jones liquids. In order to examine the effect of the attractive term on the static and dynamic properties of liquids, the energy parameter ε,22 of the second component is assumed to be twice that (ε11) of the first component, whereas the size σ and mass m of both components remain the same. The three mixtures with different combining rule for ε12 are (1) the association model (ε12 = ε11), (2) Lorentz‐Berthelot mixture (ε12 = (ε11 · ε22)1/2), and (3) the solvation model (ε12 = ε22), respectively. Both the radial distribution functions, g11, g22, and g12, and the thermodynamic excess energies have been obtained and comparisons have been made with current liquid state concepts and solution theories. It is found that the association model shows the most drastic change in g12.

What is "liquid"? Understanding the states of matter

Liquids exist in a relatively small part of the enormous range of temperatures and pressures existing in the universe. Nevertheless, they are of vital importance for physics and chemistry, for technology, and for life itself. A century of effort since the pioneering work of van der Waals has led to a fairly complete basic understanding of the static and dynamic physicochemical properties of liquids. Advances in statistical mechanics (the fundamental formulations of Gibbs and Boltzmann, integral equations and perturbation theories, computer simulations), in knowledge of intermolecular forces, and in experimental techniques; have all contributed to this. Thirty years ago the very existence of liquids seemed a little mysterious; today one can make fairly precise predictions of the solid-liquid-gas phase diagram and of the microscopic and macroscopic static and dynamic properties of liquids. This paper is a survey, with particular emphasis on equilibrium properties, of the theory which underlies that basic understanding, which is now at least comparable with our understanding of the physics of solids.

A general kinetic theory of liquids; the molecular distribution functions.

This paper outlines a general theory whose object is to provide a basis from which all the equilibrium and dynamical properties of liquids can be investigated. A set of multiform distribution functions is defined, and the generalized continuity equations satisfied by these functions are derived. By introducing the equations of motion, a set of relations is obtained from which the distribution functions may be determined. It is shown that Boltzmann’s equation in the kinetic theory of gases follows as a particular case, and that, in equilibrium conditions, the theory gives results consistent with statistical mechanics. An integral equation for the radial distribution function is obtained which is the natural generalization of one obtained by Kirkwood for ‘rigid spherical molecules’. Finally, it is indicated how the theory may be applied to solve both equilibrium and dynamical problems of the liquid state.