Hight pressure values in graphyne sheet

[fcasilva]

GROMACS version: 2022
GROMACS modification: no

Hello everyone!

I’m attempting to simulate a system that includes a graphyne sheet with water, K, and Cl ions at a concentration of 1 molar, under conditions of 300K and 1 bar pressure. The graphyne sheet was previously relaxed using DFT calculations. I acquired the GAFF force field parameters using the Antechamber tool. However, during an NPT simulation with anisotropic pressure in the Z direction, the average pressure fluctuates around 40,000 bar. To troubleshoot, I conducted tests by simulating the solution with the graphyne sheet separated, and it seems that the high-pressure issue originates from the graphyne sheet. I tried switching the force field to CHARMM, but the problem persists. Even in simulations involving only the graphyne and water, the pressure problem persists, although the water density converges to a value close to the experimental one.

I’m seeking guidance on how to resolve this pressure issue. Does anyone have any tips or advice?

P.S. The graphyne sheet is fully restrained (completely frozen), and the charges are set to zero.

Thank you!

[FarzaneJP]

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