Hi,
I have problems converging the geometry optimization of a surface model.
I get huge drift forces (>13 eV/A) although:
- all atomic forces are below the convergence thresold (<0.02 eV/A)
- all forces cancel out by symmetry (I also added them up in a spreadsheet and the result for each xyz coordinate is 0)
I tried every trick in the vasp handbook with no result in the calculation whatsoever:
- I increased NGX,NGY,NGZ values to avoid wrap-around errors
- I set up the ENCUT above the minium value in the POTCAR file (I always do)
- I increased the number of K points
I'm quite puzzled about this. What else could I do ?
Thanks a lot for your help.
Yours,
MCV
Huge drift forces
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Huge drift forces
Last edited by MCV on Thu Jan 10, 2013 5:51 pm, edited 1 time in total.
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Huge drift forces
the drift in forces usually indicates that the basis size should be increased.
please set ENCUT to at least 1.3 * max (ENMAX) of the POTCARS
please set ENCUT to at least 1.3 * max (ENMAX) of the POTCARS
Last edited by admin on Tue Jan 15, 2013 4:32 pm, edited 1 time in total.