| Re: the SCF steps is so much on each EF step.... ( No.1 )|
- Date: 2007/09/25 17:05
- Name: T.Ozaki
It is noted that the DC method solves approximately the eigenvalue problem
in O(N) operation. And if the parameters for the DC method are too inaccurate,
such a behaviour can be expected. In this case, since the charge density is
inaccurately evaluated, the Hartree potential evaluated by Poisson's equation
becomes inconsistent with the charge density calculated by the DC method,
leading to many SCF iterations.
As the parameters are set severely, it is expected that the situation becomes better.
| Unable to converge properly ( No.2 )|
- Date: 2007/10/22 21:14
- Name: asaaravind <email@example.com>
I am a new user of openmx and I am doing a geometry optimization of GaN nano wire with 180 atoms...
These are my SCF parameters...
scf.XcType GGA-PBE # LDA|LSDA-CA|LSDA-PW|GGA-PBE
scf.SpinPolarization off # On|Off|NC
scf.ElectronicTemperature 300.0 # default=300 (K)
scf.energycutoff 500.0 # default=150 (Ry)
scf.maxIter 100 # default=40
scf.EigenvalueSolver cluster # DC|GDC|Cluster|Band
scf.Kgrid 1 1 1 # means n1 x n2 x n3
scf.Mixing.Type rmm-diis # Simple|Rmm-Diis|Gr-Pulay|Kerker|Rmm-Diisk
scf.Init.Mixing.Weight 0.30 # default=0.30
scf.Min.Mixing.Weight 0.001 # default=0.001
scf.Max.Mixing.Weight 0.400 # default=0.40
scf.Mixing.History 7 # default=5
scf.Mixing.StartPulay 15 # default=6
scf.criterion 1.0e-10 # default=1.0e-6 (Hartree)
I am not able to get forces and energies converged ...
Could you please tell me waht is wrong in my input settings,
Thanks in Advance,