Editing NERD force field

The '''NERD''' force field for [[Realistic models#alkanes |alkanes]] was developed by  '''N'''ath,  '''E'''scobedo, and  '''d'''e Pablo (Ref. 1) (with the addition of the word '''R'''evised one arrives at NERD, see reference 15 within Ref. 1. The amusing nature of the name in English was far from lost on the authors). The NERD
parameters show a certain similitude to other alkane parameter sets, such as those of Smit, Karaborni, and Siepmann (SKS) (Refs. 2-4), or those of Vega et al.  Refs. 5 and 6.
In the NERD model the non-bonded [[intermolecular pair potential]] is that of the [[Lennard-Jones model]] with the following parameters (Ref. 1 Table I):
:{| border="1"
|- 
| Molecule  || <math>\sigma_{\mathrm {CH}_3}</math> ||  <math>\sigma_{\mathrm {CH}_2}</math>  ||  <math>\epsilon_{\mathrm {CH}_3}</math>  ||  <math>\epsilon_{\mathrm {CH}_2}</math> 
|- 
| [[ethane]] || 3.825 <math>\mathrm{\AA}</math> || 3.93 <math>\mathrm{\AA}</math> || 100.6 K
|- 
| [[propane]] || 3.857 <math>\mathrm{\AA}</math> || 3.93 <math>\mathrm{\AA}</math> || 102.6 K || 45.8 K
|- 
| [[butane]] and longer  || 3.91 <math>\mathrm{\AA}</math> || 3.93 <math>\mathrm{\AA}</math> || 104.0 K
|| 45.8 K
|}

==References==
#[http://dx.doi.org/10.1063/1.476429 Shyamal K. Nath, Fernando A. Escobedo, and Juan J. de Pablo "On the simulation of vapor–liquid equilibria for alkanes", Journal of Chemical Physics '''108''' pp. 9905- (1998)]
#[http://dx.doi.org/10.1063/1.469563 Berend Smit, Sami Karaborni, and J. Ilja Siepmann "Computer simulations of vapor–liquid phase equilibria of n-alkanes", Journal of Chemical Physics '''102''' pp.  2126- (1995)]
##[http://dx.doi.org/10.1063/1.476536 Berend Smit, Sami Karaborni, and J. Ilja Siepmann "Erratum: "Computer simulations of vapor–liquid phase equilibria of n-alkanes"", Journal of Chemical Physics '''109''' p. 352 (1998)]
#[http://dx.doi.org/10.1021/ja00067a088 J. Ilja Siepmann, Sami Karaborni, and Berend Smit "Vapor-liquid equilibria of model alkanes", Journal of the American Chemical Society '''115''' pp.  6454-6455 (1993)]
#[http://dx.doi.org/10.1038/365330a0 J. IIja Siepmann, Sami Karaborni and Berend Smit "Simulating the critical behaviour of complex fluids", Nature '''365''' pp. 330-332 (1993)]
#[http://dx.doi.org/10.1063/1.472291  Carlos Vega and Antonio López Rodríguez "Second virial coefficients, critical temperatures, and the molecular shapes of long n-alkanes", Journal of Chemical Physics '''105''' pp. 4223- (1996)]
#[http://dx.doi.org/10.1063/1.479283 A. Lopez Rodriguez, C. Vega and J. J. Freire "Determination of potential parameters for alkanes",  Journal of Chemical Physics '''111''' pp. 438- (1999)]
[[category:Force fields]]