Solving the Gibbs free energy of liquid water through thermodynamic integration

[kylekk01]

Dear Developers,

Here are two questions on Gibbs free energy of liquid water based on the paper (Phase Diagram of a Deep Potential Water Model).

Firstly, I noticed that a cell containing 256 water molecules was used to calculate the Gibbs free energy of liquid water. Could you please clarify whether this box was created as a new cubic water box or if it was a supercell of your training set (128 water molecules) followed by an NPT-iso simulation?

Secondly, regarding the calculation of entropy in the free energy, I am curious how to calculate it by the thermodynamic integration. Additionally, I have observed that the DPTI module contains information related to the calculation of ice phase boundaries (https://www.yuque.com/dpti/manual/gkrez8). I am wondering if there are some examples for calculating the liquid models.

Thank you for your time and assistance.