[Pw_forum] constraints in the ionic dynamics

[alan chen]

To whom it may concern,
      I am trying the CONSTRAINTS card for ionic dynamics. One of the
'constr_type' is 'distance'. However, if the distance of the two atoms I
want to fix is larger than 'dmax' (dmax is half the shortest edge of the
cell), the code crashes.
      I would like to ask why we can not fix two atoms whose distance is NOT
larger than 'dmax'? Does the algorithm not work well if the distance of two
atoms to be fixed is too large?
      Thank you very much.

Hanghui

                                             Department
of Physics,

Yale University
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20071108/06d06045/attachment.html>