[Pw_forum] metallic or not

[Sergey Lisenkov]

 Dear all,

  I have a problem. I am stdying the silicon clathrates. One of them has became metallic after full relaxation using pwscf (2.1.5 version). It is well known that silicon clathrates have band gap wider than tetrahedral silicon.

 What can be the problem?

  Thanks,
   Sergey