[gmx-users] What is the right way to get reasonable interfacial tension of surfactant at oil/water interface

Dear Gromacs users, I have do simulation of surfactant at oil/water interface for a long time. But I find it too difficult to get a reasonable interfacial tension. The key question is the pcoupltype. My system: Box size: 3.0 * 3.0 * 13 Molecule Number: decane 230, water 2041 pcoupltype =

[gmx-users] What is the right way to get reasonable interfacial tension of surfactant at oil/water interface

Dear Hugh: I can't answer your question, but I can address the error message that you see. Basically, your semi-isotropic pressure coupling allows the surface area of the water-decane interface to get smaller as z increases and x and y decrease. In a system with only water and decane, this

[gmx-users] What is the right way to get reasonable interfacial tension of surfactant at oil/water interface

Dear Chris: Thank you for your help. Maybe I can try it as this. First set x and y fixed by setting compressibility = 0 4.5e-0.5 until the system reaching equilibrium and then release. If it sounds reasonable. I am trying to do it. Dear Hugh: I can't answer your question, but I can address the

[gmx-users] What is the right way to get reasonable interfacial tension of surfactant at oil/water interface

No, the point is that the equilibrium surface area is near zero in the context of PBC and you need special tricks to keep the system away from that equilibrium. There will always be a force toward reducing the surface area of the hydrophobic/hydrophilic interface. It is possible to disallow

Re: [gmx-users] What is the right way to get reasonable interfacial tension of surfactant at oil/water interface

Very thank you for your suggestion and being so kind. I will write a new detailed subject and explain my purpose. On Sat, Jun 2, 2012 at 10:23 AM, Christopher Neale chris.ne...@mail.utoronto.ca wrote: No, the point is that the equilibrium surface area is near zero in the context of PBC and