Determination of a Three Parameter Pair Potential from Second Virial Coefficients: Ar, Kr, and Xe

1972 ◽  
Vol 57 (12) ◽  
pp. 5098-5107 ◽  
Author(s):  
Bruce W. Davis
Keyword(s):  
Pair Potential ◽  
Virial Coefficients ◽  
Second Virial Coefficients

MODELING THERMOPHYSICAL PROPERTIES OF NOBLE GAS INVOLVED MIXTURES

2011 ◽  
Vol 08 (01) ◽  
pp. 19-39 ◽  
Author(s):  
MOHAMMAD MEHDI PAPARI ◽  
JALIL MOGHADASI ◽  
SOUDABEH NIKMANESH ◽  
ELHAM HOSSEINI ◽  
ALI BOUSHEHRI
Keyword(s):  
Thermal Conductivity ◽  
Potential Energy ◽  
Thermophysical Properties ◽  
Noble Gas ◽  
Pair Potential ◽  
Virial Coefficients ◽  
Model Potential ◽  
Intermolecular Potential ◽  
Inversion Method ◽  
Second Virial Coefficients

The present work involves in determining isotropic and effective pair potential energy of binary gas mixtures of Kr–Xe , Kr–C2H6 , Xe–C2H6 , Kr–C3H8 , and Xe–C3H8 from thermophysical properties consisting of viscosity and second virial coefficients through inversion method. Typically, the calculated intermolecular potential energy of Kr–Xe system has compared with HFD model potential reported in literature. A desirable harmony between our model potential and HFD model has been obtained. In order to assess the potential energies obtained, transport properties including viscosity, diffusion, thermal diffusion factor, and thermal conductivity of aforementioned mixtures were predicted using the calculated models potential. The deviation percentage of the calculated viscosity and thermal conductivity of above-mentioned mixtures from the literature values are, respectively, within ±2%, ±3%.

On the determination of intermolecular energies by inductive analysis

1942 ◽  
Vol 38 (2) ◽  
pp. 224-230
Author(s):  
William J. C. Orr
Keyword(s):  
Virial Coefficients ◽  
Intermolecular Potential ◽  
Rare Gases ◽  
Second Virial Coefficients ◽  
Classical Expression ◽  
The Individual ◽  
Image Position ◽  
Range Of Values ◽  
Inductive Analysis

For a direct comparison of the individual attractive and repulsive terms of an intermolecular potential determined by the inductive analysis of themodynamic data with the same terms calculated by quantal methods it is desirable to carry out the analyses, in the first approximation, with an intermolecular potential of the form ø(R) = Pe−aR − A1/R6 − A2/R8. For mathematical convenience, in place of the above expression, two potential functions,andare considered, the first being taken to be adequate in the range of values of R between 0 and R0 (the minimum of the potential function) and the second, in the range from R0 to ∞. By dividing the problem in this way it is possible to find substitutions which permit the integration of the classical expression for the second virial coefficients (and other appropriate thermodynamic data) directly in terms of fairly simple series in | ψ0 |, R0, a and r. Finally it is pointed out that for such simple atoms or molecules as the rare gases, oxygen, nitrogen and methane r may be taken as 0·15 throughout, which considerably simplifies the application of the method to the experimental data.

A modification of the Redlich-Kwong-Soave equation of state and the determination of its parameters on the basis of saturated vapour pressures and second virial coefficients of pure substances

1989 ◽  
Vol 54 (6) ◽  
pp. 1446-1463 ◽  
Author(s):  
Petr Voňka ◽  
Pavel Dittrich ◽  
Josef P. Novák
Keyword(s):  
Equation Of State ◽  
Virial Coefficients ◽  
Effective Algorithm ◽  
Liquid Equilibrium ◽  
Second Virial Coefficients ◽  
Saturated Vapour ◽  
Pure Substances ◽  
Better Than ◽  
Wagner Equation

The temperature dependence of parameter a = a(Tr) of the Redlich-Kwong-Soave equation of state was modified. To calculate the corresponding individual parameters, an effective algorithm applying the Newton method was proposed. The parameters were determined for 60 substances, and the new modification correlates saturated vapour pressures from the values of pr = 0.001 to pr = 1.0 with the accuracy which is usually better than 0.2% and is comparable with that attained in terms of the Wagner equation. The modification proposed is utilized above all when applying the equation of state to the calculation of vapour-liquid equilibrium.

scholarly journals Applications of the second virial coefficient: protein crystallization and solubility

2014 ◽  
Vol 70 (5) ◽  
pp. 543-554 ◽  
Author(s):  
William W. Wilson ◽  
Lawrence J. DeLucas
Keyword(s):  
Membrane Proteins ◽  
Protein Crystallization ◽  
Second Virial Coefficient ◽  
Virial Coefficients ◽  
Protein Crystal ◽  
Second Virial Coefficients ◽  
History Of ◽  
Technological Improvements ◽  
Diagnostic Indicator

This article begins by highlighting some of the ground-based studies emanating from NASA's Microgravity Protein Crystal Growth (PCG) program. This is followed by a more detailed discussion of the history of and the progress made in one of the NASA-funded PCG investigations involving the use of measured second virial coefficients (Bvalues) as a diagnostic indicator of solution conditions conducive to protein crystallization. A second application of measuredBvalues involves the determination of solution conditions that improve or maximize the solubility of aqueous and membrane proteins. These two important applications have led to several technological improvements that simplify the experimental expertise required, enable the measurement of membrane proteins and improve the diagnostic capability and measurement throughput.

Calculation of Thermodynamical, Transport and Structural Properties of Neon in Liquid and Supercritical Phases by Molecular Dynamics Simulations Using an Accurate ab initio Pair Potential

2003 ◽  
Vol 68 (3) ◽  
pp. 627-643 ◽  
Author(s):  
Muthusamy Venkatraj ◽  
Markus G. Müller ◽  
Hanspeter Huber ◽  
Robert J. Gdanitz
Keyword(s):  
Molecular Dynamics ◽  
Ab Initio ◽  
Structural Properties ◽  
Pair Potential ◽  
Virial Coefficients ◽  
Energy Curve ◽  
Second Virial Coefficients ◽  
Analytical Potential ◽  
Supercritical Phase ◽  
Dynamics Simulations

An analytical potential energy curve (NE3) is constructed from points obtained by accurate ab initio calculations. The quality of the pair potential is established by a comparison of calculated and experimental second virial coefficients as a function of temperature. Molecular dynamics equilibrium simulations are performed with the NE3 potential for pressures between 20 and 1000 MPa and temperatures between 100 and 600 K in the supercritical phase and for one point in the liquid phase of neon. The properties are compared with those obtained from experiment. It is found that the accurate pair potential has a large effect on pressure, energies and enthalpies and a significant influence on other thermodynamic properties but little influence on transport and structural properties. In the supercritical phase the deviation between the calculated quantum-corrected and experimental pressure values is always less than 2%.

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