Hello koh seng
                            
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                                                Posted:
                            
                                9 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:
                            
                                9 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