drfit and forces dont seem to match

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Franky
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drfit and forces dont seem to match

#1 Post by Franky » Thu Oct 05, 2006 9:27 am

Just a simple question:

In my calculation the total-drift in z-direction isnt the same as the sum over all z-components of the forces (x and y likewise).
Why is that?

If I understand the source code right, this should however be the case.
What am I missing?

Thx for answering.
Last edited by Franky on Thu Oct 05, 2006 9:27 am, edited 1 time in total.

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drfit and forces dont seem to match

#2 Post by admin » Wed Oct 18, 2006 3:12 pm

for the forces on the atoms, the drift is explicitely removed before they are written (in SUBROUTINE SYMVEC), whereas it is not done for the total drift. If the total drift is significantly larger than the foces on the atoms, your basis set most probably is too small.
Last edited by admin on Wed Oct 18, 2006 3:12 pm, edited 1 time in total.

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