[Wien] Slow convergence of charge

[Lyudmila Dobysheva]

On 16.12.2014 12:53, Shafqat Hussain Shah wrote:
> Even if I do a simple scf calculation with
> MSR1, the charge does not converge with -cc 0.001 for about 200
> iterations.

Here I do not quite understand you: in the first letter you have written 
that you "have successfully optimized the volume and various ratios of 
lattice parameters of an orthorhombic system (Bi2Fe4O9) without any problem"
So you must have the converged solution with the minimum energy at some 
set of lattice parameters. Why then you have large :DIS in the first 
iteration?
Here is what I usually have in the end of the preliminary convergence 
(20 iterations without MSR1a):
:DIS:( 0.0124887 for atom 4 spin 1) 0.0030037
:DIS:( 0.0050306 for atom 4 spin 1) 0.0021021
:DIS:( 0.0054556 for atom 1 spin 1) 0.0019236
:DIS:( 0.0211810 for atom 4 spin 1) 0.0046004
:DIS:( 0.0183071 for atom 4 spin 1) 0.0025405
And this is a beginning of MSRa procedure (21th and the next iterations):
:DIS ( 0.0044783 for atom 4 spin 1) 0.0009972
:DIS ( 0.0037457 for atom 4 spin 1) 0.0009896
:DIS ( 0.0014455 for atom 2 spin 1) 0.0005299
:DIS ( 0.0020608 for atom 3 spin 1) 0.0007989

Best regards
   Lyudmila Dobysheva
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