Dear Pablo, the convergence check on stress tests EACH component against the threshold your stress tensor is not yet converged. sigma_xx and sigma_yy are NOT converged HTH stefano de Gironcoli
Pablo Aguado wrote: > I'm sorry, but I still can't see the problem ... > > forc_conv_thr = 1.0d-3 is satisfied ==> conv_ions = true > > Only z is allowed to relax (cell_dofree = 'z') so: > sigma_xx & sigma_yy should be set to 0 at some point > sigma = 0.87 Kbar > press_conv_thr = epsp = 1.0 Kbar > press = 0.0 > > so conv_ions.AND.(ABS( sigma(i,i) - press) * uakbar < epsp) is true, > unless the program is still considering stress_xx and stress_yy > (cell_dofree is not being taken into account) > > Pablo > > > On Wed, Sep 2, 2009 at 1:03 PM, Paolo Giannozzi<giannozz at democritos.it> > wrote: > >> Pablo Aguado wrote: >> >> >>> All I can say is that it seems to be converged >>> >> "it seems" /= "it is" >> >> >>> press_conv_thr = 1.0d0 >>> >> this is internally called "epsp" >> >> >>> total stress (Ry/bohr**3) (kbar) P= >>> -0.84 >>> -0.00001150 0.00000000 0.00000000 -1.69 0.00 0.00 >>> 0.00000000 -0.00001150 0.00000000 0.00 -1.69 0.00 >>> 0.00000000 0.00000000 0.00000591 0.00 0.00 0.87 >>> >> and this is where the convergence is checked: PW/vcsmd.f90, line 212 >> and following: >> >> DO i = 1, 3 >> ! >> conv_ions = conv_ions .AND. & >> ( ABS( sigma(i,i) - press) * uakbar < epsp ) >> ! >> DO j = ( i + 1 ), 3 >> conv_ions = conv_ions .AND. & >> ( ABS( sigma(i,j) ) * uakbar < epsp ) >> END DO >> ! >> END DO >> >> press=external pressure, sigma=stress tensor, >> uakbar=atomic units to KBar conversion factor. >> >> > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum >
