Calculation Not Converging
Posted: Fri Nov 26, 2010 11:33 am
Hi All,
I have problem in one of my calculation.
I set up NSW=220 and upto 50 iterations, the energy get decreased,
but after that it remains the same for the remaining upto 220 steps.
I find that the calculation is not towards convergence.
I post my INCAR here
------------------
System = silico di oxide
! 0=new, 1=wave (d), 2=same cutoff&latt (1&2 need WAVECAR file)
ISTART=1
! 0=wave (d), 1=CHGCAR
ICHARG=1
NPAR = 8
! how is parallelization done
LPLANE = .TRUE.
ENCUT= 400.00 eV
ENAUG= 700.00 eV
LREAL = auto
! use real space projection of PPs
!ROPT = 2e-4 2e-4
! prec of real space projection; repeat for each species
PREC = Accurate
! sets cutoff and FFT grid; Normal | Accurate | High; if High, sets ROPT=2e-4 automatically
ALGO = Fast
NSIM =5
! RMM-DIIS algorithm (IALGO=48) works in a blocked mode; NSIM bands are optimized at the same time. This allows to use matrix-matrix operations instead of matrix-vector operation for the evaluations of the non local projection operators in real space, and might speed up calculations on some machines
! wrap-around error warned
NGX = 66
NGY = 66
NGZ = 269
ENMAX=400
!IDIPOL = 4
NBANDS = 600
!NELM = 100
EDIFF=1e-5 ! converge force better
ISMEAR=0
SIGMA=0.01
ISPIN=2
!MAGMOM=2 2 2 2 2 2 2 2
!ISIF = 2 ! 0: relax ions, 1,2:relax ions,calc stresses, 3:relax ion+cell
NUPDOWN=0
NSW=220 !!!! Do not relax for now !!!
IBRION = 2 ! 1: quasi-NR, 2: CG algorithm for ions; use 2 for first run
!POTIM = 0.4 ! time step
EDIFFG=-0.05
!NFREE = 10 ! number of DIIS vectors to save
! write wavefunction
LWAVE=.TRUE.
! write chg and chgcar
LCHARG=.TRUE.
------------------
i post my section of OSZICAR (Even after 43 cycles)
it starts oscillating.
37 F= -.91201753E+03 E0= -.91201326E+03 d E =0.117839E+03 mag= 0.0000
38 F= -.91206963E+03 E0= -.91206538E+03 d E =0.117787E+03 mag= 0.0000
39 F= -.93866492E+03 E0= -.93866107E+03 d E =0.911913E+02 mag= 0.0000
40 F= -.10409960E+04 E0= -.10409958E+04 d E =-.111398E+02 mag= 0.0000
41 F= -.91270778E+03 E0= -.91270373E+03 d E =0.128288E+03 mag= 0.0000
42 F= -.91218044E+03 E0= -.91217619E+03 d E =0.128816E+03 mag= 0.0000
43 F= -.91218047E+03 E0= -.91217625E+03 d E =0.128816E+03 mag= 0.0000
44 F= -.91218116E+03 E0= -.91217695E+03 d E =0.128815E+03 mag= 0.0000
45 F= -.91218140E+03 E0= -.91217729E+03 d E =0.128815E+03 mag= 0.0000
46 F= -.91218162E+03 E0= -.91217742E+03 d E =0.128814E+03 mag= 0.0000
47 F= -.91218170E+03 E0= -.91217749E+03 d E =0.128814E+03 mag= 0.0000
48 F= -.91218172E+03 E0= -.91217750E+03 d E =0.128814E+03 mag= 0.0000
49 F= -.91218175E+03 E0= -.91217752E+03 d E =0.128814E+03 mag= 0.0000
50 F= -.91218177E+03 E0= -.91217771E+03 d E =0.128814E+03 mag= 0.0000
51 F= -.91218177E+03 E0= -.91217755E+03 d E =0.128814E+03 mag= 0.0000
52 F= -.91218177E+03 E0= -.91217766E+03 d E =0.128814E+03 mag= 0.0000
53 F= -.91218177E+03 E0= -.91217756E+03 d E =0.128814E+03 mag= 0.0000
54 F= -.91218177E+03 E0= -.91217760E+03 d E =0.128814E+03 mag= 0.0000
55 F= -.91218177E+03 E0= -.91217756E+03 d E =0.128814E+03 mag= 0.0000
56 F= -.91218177E+03 E0= -.91217757E+03 d E =0.128814E+03 mag= 0.0000
57 F= -.91218177E+03 E0= -.91217757E+03 d E =0.128814E+03 mag= 0.0000
58 F= -.91218177E+03 E0= -.91217759E+03 d E =0.128814E+03 mag= 0.0000
59 F= -.91218177E+03 E0= -.91217756E+03 d E =0.128814E+03 mag= 0.0000
60 F= -.91218177E+03 E0= -.91217758E+03 d E =0.128814E+03 mag= 0.0000
61 F= -.91218177E+03 E0= -.91217759E+03 d E =0.128814E+03 mag= 0.0000
62 F= -.91218177E+03 E0= -.91217757E+03 d E =0.128814E+03 mag= 0.0000
63 F= -.91218177E+03 E0= -.91217757E+03 d E =0.128814E+03 mag= 0.0000
---
Any suggestions would be appreciated.
Best regards,
Muthu
I have problem in one of my calculation.
I set up NSW=220 and upto 50 iterations, the energy get decreased,
but after that it remains the same for the remaining upto 220 steps.
I find that the calculation is not towards convergence.
I post my INCAR here
------------------
System = silico di oxide
! 0=new, 1=wave (d), 2=same cutoff&latt (1&2 need WAVECAR file)
ISTART=1
! 0=wave (d), 1=CHGCAR
ICHARG=1
NPAR = 8
! how is parallelization done
LPLANE = .TRUE.
ENCUT= 400.00 eV
ENAUG= 700.00 eV
LREAL = auto
! use real space projection of PPs
!ROPT = 2e-4 2e-4
! prec of real space projection; repeat for each species
PREC = Accurate
! sets cutoff and FFT grid; Normal | Accurate | High; if High, sets ROPT=2e-4 automatically
ALGO = Fast
NSIM =5
! RMM-DIIS algorithm (IALGO=48) works in a blocked mode; NSIM bands are optimized at the same time. This allows to use matrix-matrix operations instead of matrix-vector operation for the evaluations of the non local projection operators in real space, and might speed up calculations on some machines
! wrap-around error warned
NGX = 66
NGY = 66
NGZ = 269
ENMAX=400
!IDIPOL = 4
NBANDS = 600
!NELM = 100
EDIFF=1e-5 ! converge force better
ISMEAR=0
SIGMA=0.01
ISPIN=2
!MAGMOM=2 2 2 2 2 2 2 2
!ISIF = 2 ! 0: relax ions, 1,2:relax ions,calc stresses, 3:relax ion+cell
NUPDOWN=0
NSW=220 !!!! Do not relax for now !!!
IBRION = 2 ! 1: quasi-NR, 2: CG algorithm for ions; use 2 for first run
!POTIM = 0.4 ! time step
EDIFFG=-0.05
!NFREE = 10 ! number of DIIS vectors to save
! write wavefunction
LWAVE=.TRUE.
! write chg and chgcar
LCHARG=.TRUE.
------------------
i post my section of OSZICAR (Even after 43 cycles)
it starts oscillating.
37 F= -.91201753E+03 E0= -.91201326E+03 d E =0.117839E+03 mag= 0.0000
38 F= -.91206963E+03 E0= -.91206538E+03 d E =0.117787E+03 mag= 0.0000
39 F= -.93866492E+03 E0= -.93866107E+03 d E =0.911913E+02 mag= 0.0000
40 F= -.10409960E+04 E0= -.10409958E+04 d E =-.111398E+02 mag= 0.0000
41 F= -.91270778E+03 E0= -.91270373E+03 d E =0.128288E+03 mag= 0.0000
42 F= -.91218044E+03 E0= -.91217619E+03 d E =0.128816E+03 mag= 0.0000
43 F= -.91218047E+03 E0= -.91217625E+03 d E =0.128816E+03 mag= 0.0000
44 F= -.91218116E+03 E0= -.91217695E+03 d E =0.128815E+03 mag= 0.0000
45 F= -.91218140E+03 E0= -.91217729E+03 d E =0.128815E+03 mag= 0.0000
46 F= -.91218162E+03 E0= -.91217742E+03 d E =0.128814E+03 mag= 0.0000
47 F= -.91218170E+03 E0= -.91217749E+03 d E =0.128814E+03 mag= 0.0000
48 F= -.91218172E+03 E0= -.91217750E+03 d E =0.128814E+03 mag= 0.0000
49 F= -.91218175E+03 E0= -.91217752E+03 d E =0.128814E+03 mag= 0.0000
50 F= -.91218177E+03 E0= -.91217771E+03 d E =0.128814E+03 mag= 0.0000
51 F= -.91218177E+03 E0= -.91217755E+03 d E =0.128814E+03 mag= 0.0000
52 F= -.91218177E+03 E0= -.91217766E+03 d E =0.128814E+03 mag= 0.0000
53 F= -.91218177E+03 E0= -.91217756E+03 d E =0.128814E+03 mag= 0.0000
54 F= -.91218177E+03 E0= -.91217760E+03 d E =0.128814E+03 mag= 0.0000
55 F= -.91218177E+03 E0= -.91217756E+03 d E =0.128814E+03 mag= 0.0000
56 F= -.91218177E+03 E0= -.91217757E+03 d E =0.128814E+03 mag= 0.0000
57 F= -.91218177E+03 E0= -.91217757E+03 d E =0.128814E+03 mag= 0.0000
58 F= -.91218177E+03 E0= -.91217759E+03 d E =0.128814E+03 mag= 0.0000
59 F= -.91218177E+03 E0= -.91217756E+03 d E =0.128814E+03 mag= 0.0000
60 F= -.91218177E+03 E0= -.91217758E+03 d E =0.128814E+03 mag= 0.0000
61 F= -.91218177E+03 E0= -.91217759E+03 d E =0.128814E+03 mag= 0.0000
62 F= -.91218177E+03 E0= -.91217757E+03 d E =0.128814E+03 mag= 0.0000
63 F= -.91218177E+03 E0= -.91217757E+03 d E =0.128814E+03 mag= 0.0000
---
Any suggestions would be appreciated.
Best regards,
Muthu