[QE-users] Crash "not orthogonal operation" in a vc-relax calculation

[Paolo Giannozzi]

Hi, the reason for that message is invariably the same: a crystal 
structure, usually provided via primitive lattice vectors and ibrav=0, 
that is very close to, but not exactly equal to, the one with the 
desired symmetry

Paolo

On 12/05/2022 20:39, Fnukal Frantisek wrote:
> Dear QE users,
> 
> 
> I tried to perform a vc-relax calculation on an organic structure in a hexagonal lattice (space group R -3, num 148). The structure was in its hexagonal representation and I used an automated routine to transform it to rhombohedral representation reducing the size of the structure, thus reducing the time needed (I mention this in case it could be any relevant). When processing, QE crashed with the error "not orthogonal operation". What strikes me is that before this run I successfully completed a calculation of another structure with the exact same symmetry group using the identical approach and identical calculation parameters, so I'm not quite sure as to where could I make a mistake. As the input file is rather large, I put it in the attachment.
> 
> All answers related to this error that I stumbled upon are from old QE versions with parameters that do not exist anymore and I was not able to find out how to fix this issue, or why did one calculation finish successfully while the other did not. I'm using QE version 6.4.1.
> 
> 
> Thank you for your answers, any recommendations are of great value to me.
> 
> 
> Best regards,
> 
> 
> Frantisek Fnukal
> 
> 
> UCT Prague
> 
> 
> _______________________________________________
> The Quantum ESPRESSO community stands by the Ukrainian
> people and expresses its concerns about the devastating
> effects that the Russian military offensive has on their
> country and on the free and peaceful scientific, cultural,
> and economic cooperation amongst peoples
> _______________________________________________
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users at lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users

-- 
Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222