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Dear VASP users,

I tried to calculate band structure of GaAs, but the resultant band diagram is disappointing.
I think I wrote the code properly, but I can't think about the cause of this problem on my own.
Please help me ㅜㅜ

These are input files
--------------------------------------------------------------
1. relaxation (produce CONTCAR)
*INCAR
! INITIAL
ISTART = 0
ICHARG = 2
LCHARG = .F.
LWAVE = .F.

! ELECTRONIC OPT
ENCUT = 400
ISMEAR = 0
SIGMA = 0.1
EDIFF = 1E-6

! IONIC OPT
IBRION = 2
NSW = 100
EDIFFG = -0.03
ISIF = 3

*POSCAR
GaAs
1.0
5.7400000000000000 0.0000000000000000 0.0000000000000000
0.0000000000000000 5.7400000000000000 0.0000000000000000
0.0000000000000000 0.0000000000000000 5.7400000000000000
Ga As
4 4
Direct
0.000000000 0.000000000 0.000000000
0.500000000 0.500000000 0.000000000
0.500000000 0.000000000 0.500000000
0.000000000 0.500000000 0.500000000
0.250000000 0.250000000 0.250000000
0.750000000 0.750000000 0.250000000
0.250000000 0.750000000 0.750000000
0.750000000 0.250000000 0.750000000

*POTCAR
(skip)

*KPOINTS
KP
0
M
7 7 7
0 0 0
--------------------------------------------------------------
2. SCF CALC. (produce CHGCAR & WAVECAR)
*INCAR
! INITIAL
ISTART = 0
ICHARG = 2
LCHARG = .T.
LWAVE = .T.

! ELECTRONIC OPT
PREC = Accurate
ENCUT = 400
ISMEAR = 0
SIGMA = 0.1
EDIFF = 1E-6

! IONIC OPT
IBRION = -1
NSW = 0

*POSCAR
(CONTCAR FROM STEP1)

*KPOINTS
(SAME AS STEP1)

*POTCAR
(SKIP)

-----------------------------------------------------------------
3. BAND CALCULATION (copy CHGCAR & WAVECAR from step2)
*INCAR
! INITIAL
ISTART = 1
ICHARG = 11
LCHARG = .F.
LWAVE = .F.

! ELECTRONIC OPT
PREC = Accurate
ENCUT = 450
ISMEAR = 0
SIGMA = 0.03
EDIFF = 1E-6

! IONIC OPT
IBRION = -1
NSW = 0

! DOS
LORBIT = 11

*POSCAR
GaAs
1.00000000000000
5.7624808721322411 0.0000000000000000 -0.0000000000000000
-0.0000000000000000 5.7624808721322411 0.0000000000000000
0.0000000000000000 0.0000000000000000 5.7624808721322411
Ga As
4 4
Direct
-0.0000000000000000 0.0000000000000000 -0.0000000000000000
0.5000000000000000 0.5000000000000000 -0.0000000000000000
0.5000000000000000 0.0000000000000000 0.5000000000000000
-0.0000000000000000 0.5000000000000000 0.5000000000000000
0.2500000000000000 0.2500000000000000 0.2500000000000000
0.7500000000000000 0.7500000000000000 0.2500000000000000
0.2500000000000000 0.7500000000000000 0.7500000000000000
0.7500000000000000 0.2500000000000000 0.7500000000000000

*KPOINTS
kp
30
Line
Reciprocal
0.500 0.500 0.500 !L
0.000 0.000 0.000 !G

0.000 0.000 0.000 !G
0.500 0.000 0.500 !X

0.500 0.000 0.500 !X
0.375 0.375 0.750 !K

0.375 0.375 0.750 !K
0.000 0.000 0.000 !G
-----------------------------------------------------------------------------------

Thank you for reading :O

Dear Seunghwan_Kwon,

Could you please give more detail? What is exactly the problem with the bandstructure that you obtain? Also, it would be helpful if you could provide the input files as described in the forum guidelines.