My Community

Dear All,

I have many of my calculations killed at 20th step with the followign error message.

The structure is reasonable.

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20 F= -.12191077E+04 E0= -.12191077E+04 d E =-.937501E+00 mag= 0.0000
curvature: 0.00 expect dE= 0.000E+00 dE for cont linesearch 0.000E+00
ZBRENT: fatal internal in brackting
system-shutdown; contact gK immediately

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I am curious to know why many calculations fail only at 20th step.
Any reasons shared are appreciated.

The line search algorithm got stuck at some structure; it couldn't make any progress. Try switching minimization algorithms, eg IBRION=1 with appropriate POTIM.