Re: [gmx-users] TPI Results differ in v4.5.7 and v4.6.1

I am sorry for the late follow-up on this subject. My results using PME electrostatics do not show any differences between versions 4.5.4 and 4.6.3 (I also checked with 4.6.1 and it gave the same results): https://www.dropbox.com/s/o2kswrw5eq8fcsp/plot_batch-1_pme.png I hope that you, Niels,

Re: [gmx-users] TPI Results differ in v4.5.7 and v4.6.1

I have run TPI using three versions (4.0.4, 4.5.4 and 4.6.1) and three different insertions particles: CH4 (uncharged), Cl- (negative) and Na+ (positive). All TPI were run on the same simulations of SPC water and the three particles taken from GROMOS force-field. Reaction-field was used for

Re: [gmx-users] TPI Results differ in v4.5.7 and v4.6.1

Niels, Which force-field did you use? I guess an uncharged CH4 shouldn't be giving different results for TPI when changing coulomb... Actually, coulomb is turned off if there's no charge in the particles to insert, if I remember the code correctly. João On Mon, Jun 24, 2013 at 3:40 PM, Niels

[gmx-users] TPI Results differ in v4.5.7 and v4.6.1

Hi GMX Users, We are computing the chemical potential of different gas molecules in a polymer melt with the tpi integrator. The computations are done for CO2 and CH4. The previous computations were done with v4.5.5 or 4.5.7 and gave equal results. I recently switched to gromacs version 4.6.1,

Re: [gmx-users] TPI Results differ in v4.5.7 and v4.6.1

Niels, This is very interesting. At our group, a colleague of mine and I have also identified differences in the TPI integrator between 4.0.X and 4.5.X, but we still haven't had the time to report it properly, since we are using a slightly modified version of the TPI algorithm. Instinctively, we

Re: [gmx-users] TPI Results differ in v4.5.7 and v4.6.1

Hi João, Indeed your instinct seems to be good! When switching the Coulomb-Type to Cut-Off, there doesn't seem to be a difference between 4.6 and 4.5. Apparently its an issue with the PME sum. We will investigate further. Am 24.06.2013 um 14:42 schrieb João M. Damas jmda...@itqb.unl.pt:

Re: [gmx-users] TPI Results differ in v4.5.7 and v4.6.1

If you have a solid example that reproduced the problem, feel free to file an issue on redmine.gromacs.org ASAP. Briefly documenting your experiments and verification process on the issue report page can help help developers in giving you faster feedback as well as with accepting the report as a