SSNEB is not converging
Posted: Mon Jul 28, 2014 3:29 pm
Hi,
My name is Tanmoy and I am working as a PhD student in ICAMS, Bochum, Germany. I was doing some SSNEB calculations in my system (Titanium-Tantalum) and I had some nice results. But, recently, regarding one my SSNEB calculations, I faced some problem. What I observed that my SSNEB calculation is not converging. In my other calculations NSW reached max 50 steps, but in this calculation, it goes to 500 steps i.e, it is not converging. The energy is also not changing at all in all the steps. I have tried by changing the spring forces and the MAXMOVE tag, but didn't see any improvement. I am posting my INCAR file. Please give me some suggestions.
SYSTEM = Ti2Ta2
ENCUT = 225 energy cutoff [eV]
EDIFF = 1e-4 convergence of electronic relaxation[eV]
EDIFFG = -0.010 convergence of ionic relaxation [eV]
ISMEAR = 1 smearing (-5=tetrahedron with Bloechl, N=Methfessel-Paxton order N)
SIGMA = 0.2
ISIF = 3 stress tensor calc (0=no)
IBRION = 3
POTIM = 0.0
LCHARG = .FALSE.
LWAVE = .FALSE.
NSW = 500
ISPIN = 1 spin-polarized calc (1=no, 2=yes)
IALGO = 48
ISTART = 0 start mode (0=from scratch, 1=restart, 2=restart/constant basis set)
NPAR = 4
IOPT = 3
ICHAIN = 0
IMAGES = 5
SPRING = -4.0
LCLIMB = .FALSE.
LTANGENTOLD = .FALSE.
LDNEB = .FALSE.
LNEBCELL = .TRUE.
TIMESTEP = 0.05
MAXMOVE = 0.2
ISYM = 0
My name is Tanmoy and I am working as a PhD student in ICAMS, Bochum, Germany. I was doing some SSNEB calculations in my system (Titanium-Tantalum) and I had some nice results. But, recently, regarding one my SSNEB calculations, I faced some problem. What I observed that my SSNEB calculation is not converging. In my other calculations NSW reached max 50 steps, but in this calculation, it goes to 500 steps i.e, it is not converging. The energy is also not changing at all in all the steps. I have tried by changing the spring forces and the MAXMOVE tag, but didn't see any improvement. I am posting my INCAR file. Please give me some suggestions.
SYSTEM = Ti2Ta2
ENCUT = 225 energy cutoff [eV]
EDIFF = 1e-4 convergence of electronic relaxation[eV]
EDIFFG = -0.010 convergence of ionic relaxation [eV]
ISMEAR = 1 smearing (-5=tetrahedron with Bloechl, N=Methfessel-Paxton order N)
SIGMA = 0.2
ISIF = 3 stress tensor calc (0=no)
IBRION = 3
POTIM = 0.0
LCHARG = .FALSE.
LWAVE = .FALSE.
NSW = 500
ISPIN = 1 spin-polarized calc (1=no, 2=yes)
IALGO = 48
ISTART = 0 start mode (0=from scratch, 1=restart, 2=restart/constant basis set)
NPAR = 4
IOPT = 3
ICHAIN = 0
IMAGES = 5
SPRING = -4.0
LCLIMB = .FALSE.
LTANGENTOLD = .FALSE.
LDNEB = .FALSE.
LNEBCELL = .TRUE.
TIMESTEP = 0.05
MAXMOVE = 0.2
ISYM = 0