GCMC+NVT Density of flexible CO2 at dense phase

Hi Liang,
Have you resolved this problem with gas density calculation by GCMC+NVT? Recently, I face the same problem. Compared with NIST data, the density of methane calculated by GCMC+NVT has a good match at the gas phase. However, when it turns to liquid phase with increasing pressure, the density of methane calculated by GCMC+NVT has a relative error of 10~20%.

I shut down the GCMC but NVT is still on. The result is the same as before when we run both GCMC+NVT.

Once I input the number of methane molecules in the gas phase by .data file, and NVT ensemble is applied, the calculated pressure is the same as NIST data.

Combined with your experience, I guess we missing something in the GCMC method.

So, how do we solve the issue together?

Regards,

Douglas

  1. Jan. 2020