[Pw_forum] Questions on unit cell defination!

[张 洪彬]

Dear all:
  I am trying to do some calculation on a system with space group 
R-3m(No.166). In PWgui, when I specify the ibrav parameter, I set it to be 
ibrav=4(Hexagonal and Trigonal P) and then specify atoms in a hexagonal 
unit cell and I got a right structure which can be displayed in XCrysDen, 
but I still wonder am I right to do so?

Regards
Hongbin Zhang

_________________________________________________________________
免费下载 MSN Explorer:   http://explorer.msn.com/lccn