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Hi all,

I have a 3 questions to discuss regarding GCMC by RASPA.

1) I believe that the default calculation of adsorption in RASPA is through GCMC. Is it correct?

2) If yes (refer to question 1), how does the RASPA calculating the chemical potential during the adsorption calculation (as I am not inputting any chemical potential in the input file) and I cannot see the chemical potential printed in the output file. For example, please see this tutorial example from RASPA github: https://github.com/iRASPA/RASPA2/tree/master/examples/Basic/7_Adsorption_of_Methane_in_MFI/Output/System_0

3) The GCMC is calculating the total number of molecules in porous system. If the pores are small let's say 1A, we could say that the number of molecules is equal to the adsorbed phase in that confined pore. However, if the pores are larger (let's say 3nm ~ 30A), there is a significant free gas in the system in the middle region and I believe that the total number of molecules will not correspond to the adsorbed molecules. However, RASPA is considering number of molecules = adsorbed molecules in the calculation and provide final results based on this assumption. Do you think I need to subtract the free gas molecules from the calculation to get an actual adsorption value.

I believe these are some basic  questions, but I need the clarity for generating accurate results.

Thanks,
Temoor

Hi,

I wanted to create a density profile while running my GCMC.  My system has two slabs separated by vacant pore and I wanted to see the fluid density in the middle pore. A picture of how exactly I wanted the profile is attached.  Can you please help me with that.

Thanks

When I simulate the adsorption of my fluid on the mineral surface, I set up my external pressure to 1MPa. Now, I enabled the keyword of CalculateMolecularPressure. During the simulation, I get a pressure of 12MPa instead of 1MPa. I am unsure why it is not showing 1MPa partial pressure of my fluid.

I have tried the examples provided in the RASPA manual, and they give the same overestimated pressures during adsorption. What are the possible reasons for it? Am I setting the system wrong or the pressures are fine?

When I simulate the adsorption of my fluid on the mineral surface, I set up my external pressure to 1MPa. Now, I enabled the keyword of CalculateMolecularPressure. During the simulation, I get a pressure of 12MPa instead of 1MPa. I am unsure why it is not showing 1MPa partial pressure of my fluid.

I have tried the examples provided in the RASPA manual, and they give the same overestimated pressures during adsorption. What are the possible reasons for it? Am I setting the system wrong or the pressures are fine?