[Pw_forum] Fwd: Dear Sir! Please help me PWscf

[Tone Kokalj]

On Tue, 2006-03-21 at 16:33 +0100, Paolo Giannozzi wrote:
> 
> ----------  Forwarded Message  ----------
> 
> Subject: Dear Sir! Please help me PWscf
> Date: Tuesday 21 March 2006 11:37
> From: Nguyen Ngoc Ha <nguyenhalvt at yahoo.com>
> To: giannozz at nest.sns.it
> 
>    Dear sir!
> 
> I want to use VC-Relax to calculate lattice a,b,c and
> angles. Although I've fhinished succeed job vc-relax,
> but I don't see them, output don't run with xcrysden.

The vc-relax output of QE 3.0 is written in a non-standard way, 
so xcrysden cannot understand it. This has been fixed in the CVS version. 

The fix is simple: edit the PW/vcsmd.f90, and toward the end of the file, you will see these lines:


  WRITE( stdout, * ) ' new positions in cryst coord'
  WRITE( stdout,'(A3,3X,3F14.9)') ( atm(ityp(na)), tau(:,na), na = 1, nat )
  WRITE( stdout, * ) ' new positions in cart coord (alat unit)'
  !
  CALL cryst_to_cart( nat, tau, at, 1 )
  !
  WRITE( stdout,'(A3,3X,3F14.9)') ( atm(ityp(na)), tau(:,na), na = 1, nat )
  WRITE( stdout, '(/5X,"Ekin = ",F14.8," Ryd   T = ",F6.1," K ", &
       &       " Etot = ",F14.8)') ekint, tnew, edyn + e_start


After this lines, add the line:
  
  CALL output_tau( lmovecell )
  
And recompile the program. 
The call to output_tau( lmovecell ) will make a standard output, 
and xcrysden will be able to parse it.

Regards, Tone