Re: (Maybe) fixing Vdwd3(bj) ( No.1 ) 
 Date: 2019/10/06 09:43
 Name: Kylin <kylincaster@foxmail.com>
 Dear Gonzalez,
I think I ever meet the similar problem for the simulation of UiO66 crystal. The evoking of DFTD3 gives the Nan forces for all the atoms for both "bj" and "zero" damping functions as follows. While, if I turn off the periodic (DFTD.IntDirection as 0 0 0), the simulation run smoothly.
******************************************************* MD or geometry opt. at MD = 1 *******************************************************
<Steepest_Descent> SD_scaling= 0.150011287118 <Steepest_Descent> Maximum force (Hartree/Bohr) = 0.000000000000 <Steepest_Descent> Criterion (Hartree/Bohr) = 0.000300000000
atom= 1, XYZ(ang) Fxyz(a.u.)= 10.3695 6.0212 7.8627 nan nan nan atom= 2, XYZ(ang) Fxyz(a.u.)= 10.3525 7.7512 6.2011 nan nan nan atom= 3, XYZ(ang) Fxyz(a.u.)= 10.3833 2.9109 4.6566 nan nan nan atom= 4, XYZ(ang) Fxyz(a.u.)= 10.3656 4.7021 2.9325 nan nan nan atom= 5, XYZ(ang) Fxyz(a.u.)= 12.4845 1.9944 8.5528 nan nan nan atom= 6, XYZ(ang) Fxyz(a.u.)= 8.5531 2.0201 12.4885 nan nan nan atom= 7, XYZ(ang) Fxyz(a.u.)= 7.7172 10.5339 6.2719 nan nan nan atom= 8, XYZ(ang) Fxyz(a.u.)= 5.8448 10.5304 7.8186 nan nan nan
Thus, I has to adopt DFTD2 in my current crystal simulation. The following is my script. Can anyone provide any suggestions about it. here is my script:
https://drive.google.com/open?id=1Hi2UrL6ZcTcewlPmpSWloVRaaZg8aYKL
Cheers,
Kylin

Re: (Maybe) fixing Vdwd3(bj) ( No.2 ) 
 Date: 2019/10/07 02:13
 Name: Jhon W. Gonzalez
 Hey Kylin,
Although I'm not an OpenMx developer, I think the safest option is to select the D2 approach. You can try the modification I propose (under your own risk) and compare the results.
Best,
Jhon

Re: (Maybe) fixing Vdwd3(bj) ( No.3 ) 
 Date: 2019/10/16 13:41
 Name: T. Ozaki
 Hi Jhon,
Thank you for your valuable post. In fact, that part is a program bug. I will fix it in the next release of OpenMX.
Best regards,
TO

