[QE-users] Dip in total energy during kpoint convergence testing

[Paolo Giannozzi]

It may happen. There is no reason to assume that the energy will go down 
monotonically with increasing number of k-points

Paolo

On 3/27/23 10:34, marekgocnik via users wrote:
> Hello everyone,
>    
> I would like to ask about an energy dip that occurs while finding the
> k-point convergence of TiB2 structure. The output energies are listed
> below.
>    
> k- points, total energy
> 5   -206.8480
> 7   -206.8499
> 9   -206.8494
> 11 -206.8494
> 13 -206.8495
> 15 -206.8496
>    
> As you can see, there is a dip at k=7, although this energy difference
> occurs in the 4. decimal place, still looks kind of odd. Have you got
> any experience with this phenomenon?
>    
> Have a nice day
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-- 
Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
Univ. Udine, via delle Scienze 206, 33100 Udine Italy, +39-0432-558216