[QE-users] Inconsistent energy difference between NEB and seperated geometry optimziation

[Giuseppe Mattioli]

Dear Jibiao Li
0.091 (Ry) * 13.606 = 1.238146 (eV)
The NEB output provides energies in eV! Unless the similarity between  
1.238146 and 1.2405 eV is accidental, this should be the source of the  
reported discrepancy.
HTH
Giuseppe

Quoting jibiaoli <jibiaoli at foxmail.com>:

> Hi all,
> Recently I performed geometry optimizations for two adsroption  
> structures which I used as initial and final images for the  
> subsequent NEB calculations. However, I found that the energy  
> difference obtaned from the seperated geometry optimizations is  
> different from the energy difference  between the initial and final  
> images given by the NEB calculation. The former is 0.091 eV  
> (consistent with vasp and gpaw calculations) but the latter (1.2405  
> eV) is one order higer than the former. What's wrong with my NEB  
> calculations?
>
>
> Best
>
>
> Jibiao Li
> Yantze Normal University, China



GIUSEPPE MATTIOLI
CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
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