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[you]

They are input, you set these. These probabilities are relative to each other, and they do not influence the accuracy of the computation, just the efficiency.

There is a 'help' in iRASPA ('help' menu). In principle, this is about understanding the three panes in the top-left: (I) projects, (II) scenes, (III) movie frames. If you select the second tab, you can add structures to the scene.
'File' -> 'New' -> 'Objects' -> 'Ellipsoid' and then edit the properties.

This works in raspa3 now.

I do not see the charges of the framework. How do you set these? In the input the charges for the framework appear to be zero.

First in RASPA do a Monte Carlo simulation with some particles and create the 3D density grid.
Page 172 manual:
ComputeDensityProfile3DVTKGrid yes
WriteDensityProfile3DVTKGridEvery 10000
DensityProfile3DVTKGridPoints 150 150 150

Than it creates files which can you import in iRASPA.

In RASPA3, it will write out a cube-file, which you can also import in iRASPA.

Use a restart-file:
Reads the positions, velocities, and force from the directory 'RestartInitial'. Any creation of molecules in the 'simulation.input' file will be in addition and after this first read from file. This is useful to loadinitial positions of cations for example, and after that create adsorbates. The restart file is written at 'PrintEvery' intervals.

Easiest is to first create a system with the desired number of molecules. Then run it to get a restart-file. Move the directory from 'Restart' to 'RestartInitial' and edit the positions. Then rerun with 'RestartFile yes' (and set 'CreateNumberOfMolecules 0' since they now come from the restart-file).

Different between what and what? What is the expected value and you're getting a wrong value? More info is needed.

Under "Appearances" you have "Volumetric data": click "Show grid data" and set rendering method to "isosurface".

No, you cannot get the energy per molecule, only the total energy of the component. Note however, that all molecules are equivalent, so you could just divide by the amount of molecules.

The pressure of the liquid-phase contains a large error (because of the strong molecular interactions). Usually people take the gas-phase value after the simulation is equilibrated.

I copied your input, and see no problems.
Have you tried to run it with zero cycles? Does it finish? is the output precisely (pseudo-atoms, force field etc) exactly what you put in?
If that works, run it with 10 cycles and see if it works.

One thing that could go wrong is that your input files are not ascci-files, but utf8 or windows-files that contain different newlines.
With utilities like 'dos2unix' and 'unix2dos' you convert between windows and linux/Mac.

You're swapping molecules in and out, and hence use the grand-canonical ensemble. In this ensemble, you fix the chemical potential (via the pressure/fugacity) and the amount of molecules fluctuates. So you're not able to control how many of where the molecules are. But that is the nature of adsorption.


Btw. you're missing a rotation move (although you could say this is also achieved via insertion of molecules, this is much less efficient).

MD always uses a shifted potential. Did you use the same in the Monte Carlo?
Did you use appropriate MC moves like translation, rotation, reinsertion, partial reinsertion to sample to the phase-space properly?

RASPA is not a parallel code. There is usually very little reason to in Monte Carlo. Once your system is equilibrated, you can start several independent jobs and just average the results.

There is a example in: examples/Tutorial/AdsorptionN2InMIL-47/3-Surface-area

Output:

Average Surface Area:
=====================
        Block[ 0] 252.784946 [-]
        Block[ 1] 253.629130 [-]
        Block[ 2] 253.098236 [-]
        Block[ 3] 254.806589 [-]
        Block[ 4] 253.473192 [-]
        ------------------------------------------------------------------------------
        Average surface area:   253.558418 +/- 1.379919 [A^2]
                                1652.157533 +/- 8.991397 [m^2/g]
                                1652.766655 +/- 8.99471 [m^2/cm^3]

The radii are used to compute bonding in flexible frameworks.
For small rigid molecules you define the relative positions of all atoms (including for example dummy atoms).