REAL_OPT: internal ERROR

Problems running VASP: crashes, internal errors, "wrong" results.

Moderators: Global Moderator, Moderator

Locked
Message
Author
murphy
Newbie
Newbie
Posts: 12
Joined: Wed Apr 24, 2013 1:13 pm

REAL_OPT: internal ERROR

#1 Post by murphy » Wed Apr 24, 2013 1:24 pm

Dear VASP users,

I am doing the ENCUT test for a PbSe supercell containing 64 atoms.
I wanted to scane ENCUT= 200 300 350 400 450 500 600 700 800.
But after ENCUT= 600, I got the following errors consistently:

WARNING: PSMAXN for non-local potential too small
LDA part: xc-table for Pade appr. of Perdew
POSCAR, INCAR and KPOINTS ok, starting setup
WARNING: small aliasing (wrap around) errors must be expected
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32
REAL_OPT: internal ERROR: -48 -48 -48 32

My INCAR file is:

SYSTEM = PbSe

ENCUT = 600
ENAUG = 750

SIGMA = 0.1
LREAL = Auto
PREC = Medium
EDIFF = 0.0001
EDIFFG = -0.001
IBRION = 2 # atomic minimisation algorithm (2 or 1)
POTIM = 1.0 # "size" of atomic step
NSW = 0 # maximum number of atomic steps
ISIF = 7 # controls what should be optimised
ALGO = Fast

I am using 8x8x8 Gamma-centered k-mesh.
I did found a thread addressing the same problem in this forum.
But I after I changed the position of Pb and Se, the error still exists.
And seemingly I have to use the PAW-PBE potential always in this series calculation,
therefore I think I can not change the pseudopotentials.

Is 500 already enough for ENCUT scan? By the way, the error also happens in PbS, PbTe, SnTe supercells.

I do not have this problem in unit cell calculations, is this error associated with cell size or number of atoms?

Please give me some suggestions, thank you very much!

Sincerely,
Murphy
Last edited by murphy on Wed Apr 24, 2013 1:24 pm, edited 1 time in total.

User avatar
SKM
Jr. Member
Jr. Member
Posts: 54
Joined: Wed Oct 30, 2019 5:39 am
License Nr.: 5-516

Re: REAL_OPT: internal ERROR

#2 Post by SKM » Fri Nov 27, 2020 2:26 pm

hi
this thread is old. but i have same issue.
did you solve this problem? and how?

Regards

martin.schlipf
Global Moderator
Global Moderator
Posts: 132
Joined: Fri Nov 08, 2019 7:18 am

Re: REAL_OPT: internal ERROR

#3 Post by martin.schlipf » Mon Nov 30, 2020 7:46 am

I'm assuming this is the same issue as reported here
https://vasp.at/forum/viewtopic.php?f=4&t=5354

Let's keep this discussion in a single thread, please. If it is a distinct case, can you provide a set of input files to reproduce the issue?

Locked