On Monday 13 April 2009 02:32, loc duong ding wrote: > I wonder what is the critical of choosing Fermi level in Pwscf algorithm?
and I wonder what you mean. The Fermi energy calculated by PWscf for an insulator can be anywhere in the gap. Its exact location is unpredictable, irrelevant, and has no meaning anyway. The phisical Fermi energy for intrinsic semiconductors is located in the middle of the band gap (this is a textbook problem, by the way). > By?the way,?Fermi level is? equal to?the chemical potential?at?0K. So, It > is a very important physical meaning and?it must be a specific value at > 0K?in metal, semiconductor and insulator.? the Fermi energy for metals is correctly calculated (within the chosen approximation). For semiconductors and metals, see above Paolo -- Paolo Giannozzi, Democritos and Udine University
