[gmx-developers] Patch for 3DC for non-neutral systems but parallelization still has to be done

[Philip Loche]

Dear all,

we created a patch for gromacs 5.1 to correct the forces and the potential for charged systems using the EW3DC method. The equations are implemented according to 
Ballenegger et. al (http://dx.doi.org/10.1063/1.3216473). (29) for the potential and (30) for the force. We reproduced their results (section IV A and B). You can of course get the input files. The patch can be found on github:
https://github.com/PicoCentauri/gromacs/commit/0f9438494281668e0f9282765009889c209cb10f

The code works fine for a single thread but unfortunetaly fails for several. The problem is the summation over the atoms in line 535, where only the ones in the master process are included but not all. Unfortunately I’m not able to fix this. 

I also wanted to create a feature request on redmine, but currently it is not possible to register. It would be very nice if someone can help with the implementation.
Thank you and best regards,

Philip