Modified Lennard-Jones model: Difference between revisions

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(Created page with "The '''modified Lennard-Jones model''' is given by (Eq. 2 <ref>[http://dx.doi.org/10.1063/1.445633 Jeremy Q. Broughton and George H. Gilmer "Molecular dynamics investigation ...")
 
m (Corrected lexing error)
 
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\begin{array}{ll}
\begin{array}{ll}
4 \epsilon \left[ \left(\frac{\sigma}{r} \right)^{12}-  \left( \frac{\sigma}{r}\right)^6 \right]  + C_1 &  r \leq  2.3 \sigma \\
4 \epsilon \left[ \left(\frac{\sigma}{r} \right)^{12}-  \left( \frac{\sigma}{r}\right)^6 \right]  + C_1 &  r \leq  2.3 \sigma \\
C_2 \left(\frac{\sigma}{r} \right)^{12}  + C_3 \left(\frac{\sigma}{r} \right)^{6}  + C_4  \left(\frac{\sigma}{r} \right)^{2}  + C_5 &  2.3 \sigma < r < 2.5 \sigma\\
C_2 \left(\frac{\sigma}{r} \right)^{12}  + C_3 \left(\frac{\sigma}{r} \right)^{6}  + C_4  \left(\frac{r}{\sigma} \right)^{2}  + C_5 &  2.3 \sigma < r < 2.5 \sigma\\
0 &  2.5 \sigma \leq r
0 &  2.5 \sigma \leq r
\end{array} \right.
\end{array} \right.
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<math>C_3 = -68.069 \epsilon</math>  
<math>C_3 = -68.069 \epsilon</math>  
<math>C_4 = 0.083312 \epsilon</math>  
<math>C_4 = 0.083312 \epsilon</math>  
and <math>C_5 = 0.74689\epsilon</math>. THese parametrs are chosen so that the function <math>\Phi_{12}(r)</math>, as well as the first derivative, is continuous both at <math>r = 2.3\sigma</math> and <math>r = 2.5\sigma</math>.
and <math>C_5 = 0.74689\epsilon</math>. These parametrs are chosen so that the function <math>\Phi_{12}(r)</math>, as well as the first derivative, is continuous both at <math>r = 2.3\sigma</math> and <math>r = 2.5\sigma</math>.
These parameters have recently been recalculated by Asano and Fuchizaki <ref>[http://dx.doi.org/10.1063/1.4764855  Yuta Asano and Kazuhiro Fuchizaki "Phase diagram of the modified Lennard-Jones system", Journal of Chemical Physics '''137''' 174502 (2012)]</ref>, leading to
These parameters have recently been recalculated with greater precision by Asano and Fuchizaki <ref>[http://dx.doi.org/10.1063/1.4764855  Yuta Asano and Kazuhiro Fuchizaki "Phase diagram of the modified Lennard-Jones system", Journal of Chemical Physics '''137''' 174502 (2012)]</ref>, leading to
<math>C_1 = 0.0163169237\epsilon</math>,  
<math>C_1 = 0.0163169237\epsilon</math>,  
<math>C_2 = 3136.5686  \epsilon</math>  
<math>C_2 = 3136.5686  \epsilon</math>  
<math>C_3 = 68.069 \epsilon</math>  
<math>C_3 = -68.069 \epsilon</math> <ref>Note: due to a typographical error in the original ms, in Table I <math>C_3</math> appears to be positive. </ref>,
<math>C_4 =  −0.0833111261\epsilon</math>  
<math>C_4 =  -0.0833111261 \epsilon </math>  
and <math>C_5 = 0.746882273 \epsilon</math>.
and <math>C_5 = 0.746882273 \epsilon</math>.
==References==
==Virial coefficients==
The [[Virial equation of state|virial coefficients]]  up to the seventh order have been calculated for the range of temperatures <math>k_BT/\epsilon = 0.3-70</math> <ref>[http://dx.doi.org/10.1063/1.4882896  M. V. Ushcats "Modified Lennard-Jones model: Virial coefficients to the 7th order", Journal of Chemical Physics '''140''' 234309 (2014)]</ref>. See also <ref>[http://dx.doi.org/10.1063/1.4895126  M. V. Ushcats "Communication: Low-temperature approximation of the virial series for the Lennard-Jones and modified Lennard-Jones models", Journal of Chemical Physics '''141''' 101103 (2014)]</ref>.
 
==References==  
<references/>
<references/>


[[category: models]]
[[category: models]]

Latest revision as of 16:00, 14 September 2016

The modified Lennard-Jones model is given by (Eq. 2 [1]):

where , and . These parametrs are chosen so that the function , as well as the first derivative, is continuous both at and . These parameters have recently been recalculated with greater precision by Asano and Fuchizaki [2], leading to , [3], and .

Virial coefficients[edit]

The virial coefficients up to the seventh order have been calculated for the range of temperatures [4]. See also [5].

References[edit]