Dear Q.J. Wang, what Stefano Baroni says is correct: applying an electric field via Berry phase (lefield=.true.) does not work for metals. The code does no issue an error because you may still know what you are doing, e.g. using the smearing in an insulator. Or having an odd number of electrons in an isolated molecule.
In a metal a constant external field only have an effect on the surface, usually limited to 2-3 layers of atoms. Regards. -- Lorenzo Paulatto SISSA & DEMOCRITOS (Trieste) phone: +39 040 3787 511 skype: paulatz www: http://people.sissa.it/~paulatto/ *** save italian brains *** http://saveitalianbrains.wordpress.com/ ---------------------------------------------------------------- SISSA Webmail https://webmail.sissa.it/ Powered by Horde http://www.horde.org/
