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An error about unit in the user guide of plasma module

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The error is about the rates of the electron impact reactions.
If we press "F1" when the mouse focused on a "electron impact reaction", we can see the following sentences,
"For Rate coefficients either enter in the lookup table or load in from file a table of mean electron energy (eV) versus rate coefficient (SI unit: m3/s). "
I think the unit of rate coefficient used in COMSOL actually is [m3/mol/s], but I'm not sure about it.
Is there anyone who can tell me which one([m3/s] or [m3/mol/s]) is right?

4 Replies Last Post 07.10.2016, 03:50 GMT-4

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Posted: 8 years ago 05.10.2016, 05:37 GMT-4
Hi,
If you import cross ==> the unit is eV and cm^2

If you enter Forward rate constant ==> the unit is [m3/mol/s].
In publication you find rate constant in [m3/s]. You must multiply the value by Avogadro number to find [m3/mol/s].
Hi, If you import cross ==> the unit is eV and cm^2 If you enter Forward rate constant ==> the unit is [m3/mol/s]. In publication you find rate constant in [m3/s]. You must multiply the value by Avogadro number to find [m3/mol/s].

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Posted: 8 years ago 05.10.2016, 21:53 GMT-4

Hi,
If you import cross ==> the unit is eV and cm^2

If you enter Forward rate constant ==> the unit is [m3/mol/s].
In publication you find rate constant in [m3/s]. You must multiply the value by Avogadro number to find [m3/mol/s].


Thank you. But I want to know what is the Default unit when I enter a Rate Coefficient. For example, when I enter a list of electron energy VS rate coefficient,
1 1e-15
2 2e-15
3 3e-15
...
what is the unit of the second column values in COMSOL, [m3/s] or [m3/mol/s]?

Based on the COMSOL user's guide, the unit is [m3/s], and the above form of the values is OK.

BUT,
If the unit was [m3/mol/s], the second column should be mulitiplied by N_A_const and changed as
1 1e-15*N_A_const
2 2e-15*N_A_const
3 3e-15*N_A_const
....
SO, I want to know what is the default unit of the second column data in COMSOL.




[QUOTE] Hi, If you import cross ==> the unit is eV and cm^2 If you enter Forward rate constant ==> the unit is [m3/mol/s]. In publication you find rate constant in [m3/s]. You must multiply the value by Avogadro number to find [m3/mol/s]. [/QUOTE] Thank you. But I want to know what is the Default unit when I enter a Rate Coefficient. For example, when I enter a list of electron energy VS rate coefficient, 1 1e-15 2 2e-15 3 3e-15 ... what is the unit of the second column values in COMSOL, [m3/s] or [m3/mol/s]? Based on the COMSOL user's guide, the unit is [m3/s], and the above form of the values is OK. BUT, If the unit was [m3/mol/s], the second column should be mulitiplied by N_A_const and changed as 1 1e-15*N_A_const 2 2e-15*N_A_const 3 3e-15*N_A_const .... SO, I want to know what is the default unit of the second column data in COMSOL.

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Posted: 8 years ago 06.10.2016, 06:09 GMT-4
Hi,
You can't put
electron energy VS rate coefficient,
1 1e-15
2 2e-15
3 3e-15

For electron dissociation (or attachement or....) you have electron energy VS cross section ==> eV VS cm^2

For other reaction the default unit is [m3/mol/s] and you should mulitiplied by N_A_const
Hi, You can't put electron energy VS rate coefficient, 1 1e-15 2 2e-15 3 3e-15 For electron dissociation (or attachement or....) you have electron energy VS cross section ==> eV VS cm^2 For other reaction the default unit is [m3/mol/s] and you should mulitiplied by N_A_const

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Posted: 8 years ago 07.10.2016, 03:50 GMT-4
Are you a user or worker for COMSOL?
Actually for the electron impact reaction, a list of electron energy vs. rate coefficient can be loaded in COMSOL. Please see the attached picture about a snapshot of the "Settings" window.
Are you a user or worker for COMSOL? Actually for the electron impact reaction, a list of electron energy vs. rate coefficient can be loaded in COMSOL. Please see the attached picture about a snapshot of the "Settings" window.

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