[Pw_forum] calculation error about example12

[Gabriele Sclauzero]

If you give a look into the source code of gep_x subroutine you'll find the answer:

!
!  for some reason the lapack routine does not work if the diagonal elements
!  of the matrices are exactly zero. We tested these routines on
!  pc_ifc, ibmsp and origin.
!

maybe your version of the lapack subroutine is more lousy than usual and you will need to 
increase just a bit the delgep parameter (which will not influence the conductance at the 
significant digits, if it is kept small enough)

GS



Weiguang Chen wrote:
> Hi,
> 
> Another puzzle about example12 when I calculate the transmission of
> Al-wire, the last several lines of out-file is just as follows:
> 
>  E-Ef(ev), T(x2 spins) =    0.2500000   4.0000000
>   %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
> 
>      from gep_x : error #        38
> 
>      error on zggev
> 
>  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
> 
> 
> 
>      stopping ...
> 
> p0_24174:  p4_error: : 0
> 
>  the input files of example12 is right or not  , and is there any
> tricks about transmission calculation?
> 
>  Thanks very much
> 

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