[Pw_forum] Error: can"t open a connected unit

[Paolo Giannozzi]

On Saturday 14 June 2003 20:46, CLAUDIA BUNGARO wrote:
> One way to avoid the problem is to use another diagonalization
> algorithm, for example the Conjugate Gradient Diagonalization:
>
> diagonalization='cg'  (for 1.2.0 version)
>
> isolve=1              (for 1.1.2 version)

> [...]
> > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%
> >      from cdiaghg : error #        30
> >      info =/= 0
> > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%

note however that the above error message almost invariably
is a sign of something wrong in either the compilation or the 
data. From the manual:

\item {\em pw.x stops in cdiagh or cdiaghg.}
      Possible reasons:
      1) error in data, such as bad atomic positions or bad
         crystal structure/supercell; 
      2) a bad PP (for instance, with a ghost);
      3) IBM SP3: under some circumstances (typically a large number
         of k-points) we get an error in cdiaghg that is reproducible
         but disappears if we change anything in the calculation.
         We don't know what happens and why. Try to use
         conjugate-gradient diagonalization ({\tt diagonalization='cg'}).
      4) HP-Compaq alphas with {\tt cxml} libraries: try to use
         compiled Blas/Lapack (or better, Atlas) instead of those
         contained in {\tt cxml} (just load them before {\tt cxml}).

Paolo

-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
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