[Pw_forum] Strange behavior of scf calculation under finite-field

[lan haiping]

Dear All,

  I am studying electric-enthalpy method implemented in pw.x with
example31.  There are some problems i cannot solve by myself.
Firstly,  when i set "ecutrho" explictly, calculations under finite-field
are failed without any complain information, such as CRASH report. My server
is of 8GB memory, and no such crash for other scf calculations . I had tried
'cg' and 'david' methods, and cannot solve this  problems.
Secondly,  when i set occupations to 'mv' smearing scheme with degauss=0.03
a.u. , the scf calculation of finite-field situation
is very difficult to reach convergence.  I have tried to increase or
decrease mixing_ndim,  but failed.  Besides, i have tried to increase
nbnd , which seems no effect on scf convergence.  Would you please give me
some suggestion on parameters setting for scf calculation under finite-field
?

Thanks for your time and attention . Any suggestion or comment is
appreciated .

Best Wishes,
H.P



-- 
Hai-Ping Lan
Department of Electronics ,
Peking University , Bejing, 100871
lanhaiping at gmail.com, hplan at pku.edu.cn
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20070705/b3876ae9/attachment.html>