Difference between revisions of "SPC model of water"

From SklogWiki
Jump to: navigation, search
(dipole moment added)
m (Updated internal link)
Line 1: Line 1:
 
{{Stub-water}}
 
{{Stub-water}}
The '''simple point charge''' (SPC) model is an [[Empirical water models | empirical model of water]]. The molecule is modelled as
+
The '''simple point charge''' (SPC) model is an [[List of empirical water models | empirical model of water]]. The molecule is modelled as
 
a rigid isosceles triangle, having charges situated on each of the three atoms. Apart from Coulombic interactions, the molecules interact via long-range [[Lennard-Jones model | Lennard-Jones]] sites, situated  on the  oxygen atoms. The parameters are as follows:
 
a rigid isosceles triangle, having charges situated on each of the three atoms. Apart from Coulombic interactions, the molecules interact via long-range [[Lennard-Jones model | Lennard-Jones]] sites, situated  on the  oxygen atoms. The parameters are as follows:
 
[[Image:Water_empirical1.png|center|300px]]
 
[[Image:Water_empirical1.png|center|300px]]

Revision as of 12:23, 5 September 2008

Water icon.png This article is a 'stub' about water and/or ice. It has no, or next to no, content. It is here at the moment to help form part of the structure of SklogWiki. If you add material to this article, remove the {{Stub-water}} template from this page.

The simple point charge (SPC) model is an empirical model of water. The molecule is modelled as a rigid isosceles triangle, having charges situated on each of the three atoms. Apart from Coulombic interactions, the molecules interact via long-range Lennard-Jones sites, situated on the oxygen atoms. The parameters are as follows:

Water empirical1.png
parameter value
\sigma  3.166 {\mathrm {\AA}}
\epsilon 0.650 kJ mol-1
r_\mathrm{OH} 1.000\mathrm{\AA}
\angle_\mathrm{HOH} 109.47^{\circ}
q_{\mathrm{O}} -0.82 e
q_{\mathrm{H}} q_{\mathrm{O}}/2 (charge neutrality)
r_\mathrm{OM} 0 (charge sits on oxygen)

The SPC model has a dipole moment of 2.27 D.


References

  1. H. J. C. Berendsen, J. P. M. Postma, W. F. van Gunsteren and J. Hermans, in: Intermolecular Forces (B. Pullman, ed.), Reidel, Dordrecht, p. 331 (1981).