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Transport properties for COMSOL engineering lab

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I am having difficulties in obtaining the transport properties for my research.
Any idea on where can i get the potential characteristic length,the dipole moment,and also the potential energy minimum?

2 Replies Last Post 24 nov. 2016, 04:02 UTC−5
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Hello koh seng

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Posted: 8 years ago 23 nov. 2016, 10:56 UTC−5
Hi Koh Seng /comsol community,

I know, the post is over 6 years old, but I found this with google, because I have the same problem. Could you solve it or does anyone else have an idea? Can this be calculated? (I need it for WF6 and HF).

In the help is written:

"For a gas mixture, there are maximum five properties to consider: σ, the characteristic length (unit: Å) of the Lennard-Jones/Stockmayer potential; ε/kb, the energy minimum (SI unit: K) of the Lennard-Jones/Stockmayer potential; μD, the dipole moment (SI unit: Debye); ki, the thermal conductivity of the gas (SI unit: W/(m K)); and Diffusivity of the species (SI unit: m2/s). The latter two can be set as Automatic, when theoretical Transport Parameters expressions are available."

a picture showing the meaning of σ and ε:
chem.libretexts.org/@api/deki/files/8914/=Figure_B.jpg?revision=1

In Comsol it's ε divided by boltzmann constant
Hi Koh Seng /comsol community, I know, the post is over 6 years old, but I found this with google, because I have the same problem. Could you solve it or does anyone else have an idea? Can this be calculated? (I need it for WF6 and HF). In the help is written: "For a gas mixture, there are maximum five properties to consider: σ, the characteristic length (unit: Å) of the Lennard-Jones/Stockmayer potential; ε/kb, the energy minimum (SI unit: K) of the Lennard-Jones/Stockmayer potential; μD, the dipole moment (SI unit: Debye); ki, the thermal conductivity of the gas (SI unit: W/(m K)); and Diffusivity of the species (SI unit: m2/s). The latter two can be set as Automatic, when theoretical Transport Parameters expressions are available." a picture showing the meaning of σ and ε: http://chem.libretexts.org/@api/deki/files/8914/=Figure_B.jpg?revision=1 In Comsol it's ε divided by boltzmann constant

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Posted: 8 years ago 24 nov. 2016, 04:02 UTC−5
In this paper the desired values for a lot of gases can be found:
www.nrcresearchpress.com/doi/abs/10.1139/v77-418#.WDarCXpKBpc

In this paper the desired values for a lot of gases can be found: http://www.nrcresearchpress.com/doi/abs/10.1139/v77-418#.WDarCXpKBpc

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