Hard core Yukawa potential

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The repulsive form has been used to study charge-stabilised [[Colloids |colloid-colloid]] interactions.  
The repulsive form has been used to study charge-stabilised [[Colloids |colloid-colloid]] interactions.  
==Critical point==
==Critical point==
-
For the attractive form of the potential, from a study of the [[law of corresponding states]], one has (Ref. 1 Eq. 3)
+
For the attractive form of the potential, from a study of the [[law of corresponding states]], one has (Eq. 3 in <ref>[http://dx.doi.org/10.1063/1.2883694 Pedro Orea and Yurko Duda "On the corresponding states law of the Yukawa fluid",  Journal of Chemical Physics '''128''' 134508 (2008)]</ref>)
:<math>P_c = 0.0228 + 0.0742 T_c</math>
:<math>P_c = 0.0228 + 0.0742 T_c</math>
-
and (Ref. 1 Eq. 4)
+
and (Eq. 4)
:<math>\rho_c = 0.2534 + 0.071 \frac{1}{T_c}</math>.
:<math>\rho_c = 0.2534 + 0.071 \frac{1}{T_c}</math>.
The repulsive form of the potential has no critical point.  
The repulsive form of the potential has no critical point.  
==Triple points==
==Triple points==
-
#[http://dx.doi.org/10.1063/1.481068 Fouad El Azhar, Marc Baus, Jean-Paul Ryckaert and Evert Jan Meijer "Line of triple points for the hard-core Yukawa model: A computer simulation study", Journal of Chemical Physics '''112''' pp.  5121- (2000)]
+
The [[triple point |triple points]] for this model have been studied by Azhar and co-workers
 +
<ref>[http://dx.doi.org/10.1063/1.481068 Fouad El Azhar, Marc Baus, Jean-Paul Ryckaert and Evert Jan Meijer "Line of triple points for the hard-core Yukawa model: A computer simulation study", Journal of Chemical Physics '''112''' pp.  5121- (2000)]</ref>.
 +
==Virial coefficients==
 +
For the attractive form of the potential the [[Virial equation of state |virial coefficients]] have been calculated by Naresh and Singh <ref>[http://dx.doi.org/10.1016/j.fluid.2009.06.019  D.J. Naresh and Jayant K. Singh "Virial coefficients of hard-core attractive Yukawa fluids", Fluid Phase Equilibria '''285''' pp. 36-43 (2009)]</ref>.
==Phase diagram==
==Phase diagram==
:''Main article: [[Phase diagram of the Yukawa potential]]''
:''Main article: [[Phase diagram of the Yukawa potential]]''
==References==
==References==
-
#[http://dx.doi.org/10.1063/1.2883694 Pedro Orea and Yurko Duda "On the corresponding states law of the Yukawa fluid",  Journal of Chemical Physics '''128''' 134508 (2008)]
+
<references/>
[[Category: Models]]
[[Category: Models]]

Revision as of 17:14, 25 November 2009

The hard core Yukawa potential has two forms, the attractive Yukawa potential:


\Phi_{12}\left( r \right) = 
\left\{ \begin{array}{lll}
\infty & ; & r < \sigma \\
- \left( \frac{ \epsilon \sigma }{r}\right)  \exp \left[- \kappa \left( \frac{r}{\sigma} -  1 \right) \right] & ; & r \ge \sigma 
\end{array} \right.

and the repulsive form


\Phi_{12}\left( r \right) = 
\left\{ \begin{array}{lll}
\infty & ; & r < \sigma \\
\left( \frac{ \epsilon \sigma }{r}\right)  \exp \left[- \kappa \left( \frac{r}{\sigma} -  1 \right) \right] & ; & r \ge \sigma 
\end{array} \right.

where  \Phi\left( r \right) is the intermolecular pair potential, r := |\mathbf{r}_1 - \mathbf{r}_2| is the distance between site 1 and site 2, σ is the hard diameter, ε is the energy well depth (ε > 0), and κ is a parameter that controls the interaction range (κ > 0).

The repulsive form has been used to study charge-stabilised colloid-colloid interactions.

Contents

Critical point

For the attractive form of the potential, from a study of the law of corresponding states, one has (Eq. 3 in [1])

Pc = 0.0228 + 0.0742Tc

and (Eq. 4)

\rho_c = 0.2534 + 0.071 \frac{1}{T_c}.

The repulsive form of the potential has no critical point.

Triple points

The triple points for this model have been studied by Azhar and co-workers [2].

Virial coefficients

For the attractive form of the potential the virial coefficients have been calculated by Naresh and Singh [3].

Phase diagram

Main article: Phase diagram of the Yukawa potential

References

  1. Pedro Orea and Yurko Duda "On the corresponding states law of the Yukawa fluid", Journal of Chemical Physics 128 134508 (2008)
  2. Fouad El Azhar, Marc Baus, Jean-Paul Ryckaert and Evert Jan Meijer "Line of triple points for the hard-core Yukawa model: A computer simulation study", Journal of Chemical Physics 112 pp. 5121- (2000)
  3. D.J. Naresh and Jayant K. Singh "Virial coefficients of hard-core attractive Yukawa fluids", Fluid Phase Equilibria 285 pp. 36-43 (2009)
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