Dear all, I am having some difficulties related to the symmetry detection for antiferromagnetic materials in QE 7.4. I want to run a spin-polarised (collinear) structural relaxation for Ca2FeAlO5 with G-type AFM order (magnetic space group Ima’2’, number 46.244) has 2 magnetic Fe-sites in the primitive unit cell, which should have opposite magnetic moments. For this space group I am expecting 4 symmetry operations, which QE does correctly detect when running a calculation with ferromagnetic configuration (see attached files labelled with ‘FM’).
However, when running the antiferromagnetic system, I believe I have to specify the sites of opposite moments with different labels, so that I can initialize the moments by setting starting_magnetization(i) accordingly (see attached files labelled with ‘AFM’). Unfortunately, it appears that the two Fe-sites are then treated as completely distinct sites during the symmetry detection and 2 of the 4 symmetry operations cannot be found anymore even though they should be present. In particular, it seems to affect operations that involve fractional translations. I understand this limitation has been discussed previously for other AFM systems with non-symmorphic space groups (e.g. https://lists.quantum-espresso.org/pipermail/developers/2020-May/002220.html ), so I wonder whether it has been fixed yet or if there is some kind of workaround? Thanks in advance for your help and for your hard work! Best wishes, Paul Dirk
Ca2FeAlO5.AFM.in
Description: Ca2FeAlO5.AFM.in
Ca2FeAlO5.AFM.out
Description: Ca2FeAlO5.AFM.out
Ca2FeAlO5.FM.in
Description: Ca2FeAlO5.FM.in
Ca2FeAlO5.FM.out
Description: Ca2FeAlO5.FM.out
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