Issues about LKPROJ tag

[yujia_teng]

Dear admin,
I'm using band4vasp to do band and fermi surface unfolding, which requires the LKPROJ tag. But I have 2 problems that i can't solve:

1.How much memory is required for a node to perform such job? I tested it in some systems. It only works for graphene. For the 2 other examples I attached below (one of them is with SOC+U), 'forrtl: severe (174): SIGSEGV, segmentation fault occurred' is found in the log file, which means not enough memory. So OUTCAR, PROCAR and some other output files were not finished.

2.In PRJCAR file, I found the high symmetry M point isn't correct. I set 0.5 0 but it becomes -0.5 0 in the file (see GdAuGe PRJCAR file). So the plotted unfolded band has unusual long M-K path because of this jump, which is obviously wrong (band is also attatched).

[andreas.singraber]

Hello!

Since the band4vasp and UnfoldingPatch4vasp software were new to me I had a discussion today with my colleagues about this topic. Unfortunately it seems the patch never made it into the maintained VASP source code. Hence, we officially cannot offer support for the modified code and its post-processing tool. It may be a good idea to also contact the developers directly (e.g. via Github issues) to resolve your problems.

However, there is an interest from our side to integrate the additional features offered by this patch finally into future VASP versions. Also, we would like to know whether the issues you observed are coming from patched code or official VASP source code:

1. The segmentation fault can indeed be a sign of running out of memory. However, this is not the only possible cause and we would like to understand the origins of this error.

2. As with the other issue we want to know whether this problem is introduced by the patch or already present in the regular VASP code.

In case the maintained VASP source is responsible for the issues we may be able to give useful advice to avoid them.

In order to be able to accurately reproduce the behavior I would like to ask you to provide some more data:

• Please describe any preparatory steps you carry out,

• upload all relevant input and output files (also for preparatory steps),

• describe on which machines you where executing VASP (ideally add a submit script) and

• which compilers and libraries were used to build VASP (ideally add a makefile.include)

I am sorry for insisting on this rather detailed information but without it we have to do a lot of guessing and may never be able to reproduce the problems.

Thank you!

All the best,
Andreas Singraber