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SPC/E model of water

2014-12-24T17:06:44Z

Jeffcomer: Undo revision 14452 by Jeffcomer (talk)

{{Stub-water}}
The '''SPC/E''' (extended simple point charge model) UNIQ07be08afbd145544-ref-0000002B-QINU
UNIQ07be08afbd145544-ref-0000002C-QINU is a slight reparameterisation of the [[SPC]] model of [[water]], with a modified value for UNIQ07be08afbd145544-math-0000002D-QINU.
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:
[[Image:Thee_site_water_model.png‎|center|400px]]
{| border="1"
|-
| parameter || value
|-
| UNIQ07be08afbd145544-math-0000002E-QINU || UNIQ07be08afbd145544-math-0000002F-QINU Å
|-
| UNIQ07be08afbd145544-math-00000030-QINU || UNIQ07be08afbd145544-math-00000031-QINU kJ mol-1
|-
| UNIQ07be08afbd145544-math-00000032-QINU || UNIQ07be08afbd145544-math-00000033-QINU Å
|-
| UNIQ07be08afbd145544-math-00000034-QINU || UNIQ07be08afbd145544-math-00000035-QINU
|-
| UNIQ07be08afbd145544-math-00000036-QINU || UNIQ07be08afbd145544-math-00000037-QINU
|-
| UNIQ07be08afbd145544-math-00000038-QINU || UNIQ07be08afbd145544-math-00000039-QINU (charge neutrality)
|}
The SPC/E model has a [[dipole moment]] of 2.351 D. (Ref. 1 Table I).
==Surface tension==
The [[surface tension]] has been studied for the SPC/E model by Vega and Miguel
UNIQ07be08afbd145544-ref-0000003A-QINU
==Phase diagram==
[[Image:SPC_E_phase_diagram.png|right|400px]]
===Plastic crystal phases===
Recent simulations have demonstrated the existence of [[Plastic crystals | plastic crystal]] phases for the SPC/E model.
UNIQ07be08afbd145544-ref-0000003B-QINU
==Shear viscosity==
The [[shear viscosity]] for the SPC/E model is 0.729 mPa.s at 298 K and 1 bar UNIQ07be08afbd145544-ref-0000003C-QINU (experimental value 0.896 mPa.s UNIQ07be08afbd145544-ref-0000003D-QINU).

==Thermal conductivity==
[[Thermal conductivity]] UNIQ07be08afbd145544-ref-0000003E-QINU.

==References==
UNIQ07be08afbd145544-references-0000003F-QINU
;Related reading
*[http://dx.doi.org/10.1063/1.3548869 Péter T. Kiss and András Baranyai "Sources of the deficiencies in the popular SPC/E and TIP3P models of water", Journal of Chemical Physics '''134''' 054106 (2011)]
[[category: water]]
[[category: models]]

SPC/E model of water

2014-12-24T16:04:49Z

Jeffcomer: Need minus sign for charge neutrality

{{Stub-water}}
The '''SPC/E''' (extended simple point charge model) UNIQ11bf423f66a234ea-ref-0000002B-QINU
UNIQ11bf423f66a234ea-ref-0000002C-QINU is a slight reparameterisation of the [[SPC]] model of [[water]], with a modified value for UNIQ11bf423f66a234ea-math-0000002D-QINU.
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:
[[Image:Thee_site_water_model.png‎|center|400px]]
{| border="1"
|-
| parameter || value
|-
| UNIQ11bf423f66a234ea-math-0000002E-QINU || UNIQ11bf423f66a234ea-math-0000002F-QINU Å
|-
| UNIQ11bf423f66a234ea-math-00000030-QINU || UNIQ11bf423f66a234ea-math-00000031-QINU kJ mol-1
|-
| UNIQ11bf423f66a234ea-math-00000032-QINU || UNIQ11bf423f66a234ea-math-00000033-QINU Å
|-
| UNIQ11bf423f66a234ea-math-00000034-QINU || UNIQ11bf423f66a234ea-math-00000035-QINU
|-
| UNIQ11bf423f66a234ea-math-00000036-QINU || UNIQ11bf423f66a234ea-math-00000037-QINU
|-
| UNIQ11bf423f66a234ea-math-00000038-QINU || UNIQ11bf423f66a234ea-math-00000039-QINU (charge neutrality)
|}
The SPC/E model has a [[dipole moment]] of 2.351 D. (Ref. 1 Table I).
==Surface tension==
The [[surface tension]] has been studied for the SPC/E model by Vega and Miguel
UNIQ11bf423f66a234ea-ref-0000003A-QINU
==Phase diagram==
[[Image:SPC_E_phase_diagram.png|right|400px]]
===Plastic crystal phases===
Recent simulations have demonstrated the existence of [[Plastic crystals | plastic crystal]] phases for the SPC/E model.
UNIQ11bf423f66a234ea-ref-0000003B-QINU
==Shear viscosity==
The [[shear viscosity]] for the SPC/E model is 0.729 mPa.s at 298 K and 1 bar UNIQ11bf423f66a234ea-ref-0000003C-QINU (experimental value 0.896 mPa.s UNIQ11bf423f66a234ea-ref-0000003D-QINU).

==Thermal conductivity==
[[Thermal conductivity]] UNIQ11bf423f66a234ea-ref-0000003E-QINU.

==References==
UNIQ11bf423f66a234ea-references-0000003F-QINU
;Related reading
*[http://dx.doi.org/10.1063/1.3548869 Péter T. Kiss and András Baranyai "Sources of the deficiencies in the popular SPC/E and TIP3P models of water", Journal of Chemical Physics '''134''' 054106 (2011)]
[[category: water]]
[[category: models]]

SPC model of water

2014-12-24T16:02:26Z

Jeffcomer: Undo revision 14450 by Jeffcomer (talk)

The '''simple point charge''' (SPC) model
UNIQ3c9329b265030360-ref-00000015-QINU
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
|-
| UNIQ3c9329b265030360-math-00000016-QINU || UNIQ3c9329b265030360-math-00000017-QINUÅ
|-
| UNIQ3c9329b265030360-math-00000018-QINU || UNIQ3c9329b265030360-math-00000019-QINU kJ mol-1
|-
| UNIQ3c9329b265030360-math-0000001A-QINU || UNIQ3c9329b265030360-math-0000001B-QINUÅ
|-
| UNIQ3c9329b265030360-math-0000001C-QINU || UNIQ3c9329b265030360-math-0000001D-QINU
|-
| UNIQ3c9329b265030360-math-0000001E-QINU || UNIQ3c9329b265030360-math-0000001F-QINU
|-
| UNIQ3c9329b265030360-math-00000020-QINU || UNIQ3c9329b265030360-math-00000021-QINU (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.
UNIQ3c9329b265030360-ref-00000022-QINU
==Related models==
Over the years a number of variants of the SPC model have been published:
*[[SPC]]
*[[SPC/E]]
*[[SPC/F]]
*[[SPC/F2]]
*[[SPC/FP]]
*[[SPC/FQ]]
*[[SPC/Fw]]
*[[SPC/HW]]
*[[SPCP]]
*[[SPC-pol]]
==References==
UNIQ3c9329b265030360-references-00000023-QINU
[[category: water]]
[[category: models]]

SPC model of water

2014-12-24T16:01:19Z

Jeffcomer: need a negative sign for charge neutrality (or an absolute value)

The '''simple point charge''' (SPC) model
UNIQb1b2d8277abe3830-ref-00000015-QINU
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
|-
| UNIQb1b2d8277abe3830-math-00000016-QINU || UNIQb1b2d8277abe3830-math-00000017-QINUÅ
|-
| UNIQb1b2d8277abe3830-math-00000018-QINU || UNIQb1b2d8277abe3830-math-00000019-QINU kJ mol-1
|-
| UNIQb1b2d8277abe3830-math-0000001A-QINU || UNIQb1b2d8277abe3830-math-0000001B-QINUÅ
|-
| UNIQb1b2d8277abe3830-math-0000001C-QINU || UNIQb1b2d8277abe3830-math-0000001D-QINU
|-
| UNIQb1b2d8277abe3830-math-0000001E-QINU || UNIQb1b2d8277abe3830-math-0000001F-QINU
|-
| UNIQb1b2d8277abe3830-math-00000020-QINU || UNIQb1b2d8277abe3830-math-00000021-QINU (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.
UNIQb1b2d8277abe3830-ref-00000022-QINU
==Related models==
Over the years a number of variants of the SPC model have been published:
*[[SPC]]
*[[SPC/E]]
*[[SPC/F]]
*[[SPC/F2]]
*[[SPC/FP]]
*[[SPC/FQ]]
*[[SPC/Fw]]
*[[SPC/HW]]
*[[SPCP]]
*[[SPC-pol]]
==References==
UNIQb1b2d8277abe3830-references-00000023-QINU
[[category: water]]
[[category: models]]