Dear Lammps community,
First I run the in.gcmc.h2o example under the directory of examples\mc using lammps-23Jun2022, and the final data file named gcmc.data has been got. The mu value in in.gcmc.h2o is -8.1 kcal/mol.
Then I modified the flexible SPC/E in in.widom.spce into rigid SPC/E water models to keep consistent with those in.gcmc.h2o, to run Widom insertion to calculate the mu_ex. The modified in script is named in.widom.rigidspce. The data file read in is gcmc.data.
I also use the equation mu_id = K * T * ln(ρ * ∧^3) to calculate the mu_id.
From my understanding, the sum of the calculated mu_id and the simulated mu_ex should be ~8.1 kcal/mol. But the results have a large discrepancy.
The widom.log.lammps is attached, in which f_mywidom[1] is averaged as 80.5 kcal/mol. The calculated mu_id is -4.8 kcal/mol. The sum is 75.7 kcal/mol.
Related files including gcmc.data and in.widom.rigidspce are also attached. Any comments are welcome. Thank you very much.
gcmc.data (17.4 KB)
in.widom.rigidspce (918 Bytes)
widom.log.lammps (1.4 MB)
