[Pw_forum] where is the end of an unconverged NEB calculation

[vega lew]

Dear all,

During my NEB calculations, I found there are two possible situation. First,
the calculation could be converged after about 100 iterations. Second, the
calculation never converged in more than 300 iterations. And for the second
case, the energy barrier went down and down to a certain value, and then the
reported energy barrier went up gradually. For example in my resent job, the
energy barrier goes to 1.49 eV from the intial 2.99 eV in about 120
iterations. Then the energy barrier rise to 1.73 eV bit by bit in following
40 iterations. And the calculation is still running while this value is
still going up. How could I deal with this situation?  Could I take the
lowest value as the energy barrier of the reaction? How could I know whether
there will be another smaller value in the longer calculation?

thank you for reading. Ang hints will be deeply appreciated.

best,

vega

-- 
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Vega Lew ( weijia liu)
Graduate student
State Key Laboratory of Materials-oriented Chemical Engineering
College of Chemistry and Chemical Engineering
Nanjing University of Technology, 210009, Nanjing, Jiangsu, China
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Email: vegalew at gmail.com
Office: Room A705, Technical Innovation Building, Xinmofan Road 5#, Nanjing,
Jiangsu, China
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