Question about fix GCMC for calculating adsorption isotherm.


I want to calculate adsorption isotherm of gas molecule within metal organic framework, but I am not familiar with GCMC at LAMMPS

First of all, I made my system (simulation cell) with read_data, and adsorbate molecules were set using molecule command.

And using pressure keyword, I can set separate point of adsorption isotherm.

However, I don¡¯t know how to check the average number of loaded gas molecule in my system to plot adsorption isotherm.

In manual, the output of this fix just gives the information on the attempts and successes.

How can I get the information of the number of adsorbed molecules for each step or average value?

Of course, can I use this fix multiple times for more than two kinds of adsorbate molecules, simultaneously?

Eventhough I did not add my input file here, I think there will be no problem with explanation for my questions.


Best Regards,

Jeong Hyeon.

UNIST, Republic of Korea.

You can directly count the number of atoms in a group using the count() function e.g. to count water molecules, you might do:

variable M equal “count(water) / 3”

That will also match the difference between accepted insertions and accepted deletions.