SPC model of water: Difference between revisions
		
		
		
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| The '''simple point charge''' empirical [[ | The '''simple point charge''' (SPC) model | ||
| <ref>H. J. C. Berendsen, J. P. M. Postma, W. F. van Gunsteren and J. Hermans, in: Intermolecular Forces (B. Pullman, ed.), Reidel, Dordrecht (1981) p. 331 ISBN 902771326X</ref> | |||
| is an [[water models | empirical model of water]]. The molecule is modelled as | |||
| a rigid isosceles triangle, having charges situated on each of the three atoms. As well as [[Coulomb's law |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:Thee_site_water_model.png|center|400px]] | |||
| {| border="1" | |||
| |-  | |||
| | parameter || value | |||
| |-   | |||
| | <math>\sigma</math> || <math> 3.166</math>Å | |||
| |- | |||
| | <math>\epsilon</math> || <math>0.650</math> kJ mol<sup>-1</sup> | |||
| |- | |||
| | <math>r_\mathrm{OH}</math> || <math>1.000</math>Å | |||
| |- | |||
| | <math>\angle_\mathrm{HOH}</math> || <math>109.47^{\circ}</math> | |||
| |- | |||
| | <math>q_{\mathrm{O}}</math> ||  <math>-0.82 e</math> | |||
| |- | |||
| | <math>q_{\mathrm{H}}</math> ||  <math>|q_{\mathrm{O}}|/2</math> (charge neutrality) | |||
| |} | |||
| The SPC model has a [[dipole moment]] of 2.27 D. | |||
| ==Surface tension== | |||
| The [[surface tension]] has been studied for the SPC model by Vega and Miguel. | |||
| <ref>[http://dx.doi.org/10.1063/1.2715577 C. Vega and E. de Miguel "Surface tension of the most popular models of water by using the test-area simulation method", Journal of Chemical Physics '''126''' 154707 (2007)]</ref> | |||
| ==Related models== | |||
| Over the years a number of variants of the SPC model have been published: | |||
| *[[SPC/ε water model | SPC/ε]] | |||
| *[[SPC/A]] | |||
| *[[SPC/E]] | |||
| *[[SPC/F]] | |||
| *[[SPC/F2]] | |||
| *[[SPC/FP]] | |||
| *[[SPC/FQ]] | |||
| *[[SPC/Fw]] | |||
| *[[SPC/HW]] | |||
| *[[SPC/L]] | |||
| *[[SPCP]] | |||
| *[[SPC-pol]] | |||
| ==References== | ==References== | ||
| <references/> | |||
| [[category: water]] | [[category: water]] | ||
| [[category: models]] | [[category: models]] | ||
Latest revision as of 15:20, 9 February 2015
The simple point charge (SPC) model [1] is an empirical model of water. The molecule is modelled as a rigid isosceles triangle, having charges situated on each of the three atoms. As well as Coulombic interactions, the molecules interact via long-range Lennard-Jones sites, situated on the oxygen atoms. The parameters are as follows:

| parameter | value | 
| Å | |
| kJ mol-1 | |
| Å | |
| (charge neutrality) | 
The SPC model has a dipole moment of 2.27 D.
Surface tension[edit]
The surface tension has been studied for the SPC model by Vega and Miguel. [2]
Related models[edit]
Over the years a number of variants of the SPC model have been published:
References[edit]
- ↑ H. J. C. Berendsen, J. P. M. Postma, W. F. van Gunsteren and J. Hermans, in: Intermolecular Forces (B. Pullman, ed.), Reidel, Dordrecht (1981) p. 331 ISBN 902771326X
- ↑ C. Vega and E. de Miguel "Surface tension of the most popular models of water by using the test-area simulation method", Journal of Chemical Physics 126 154707 (2007)