On Wednesday 24 May 2006 18:20, John B Burdette wrote: > [...] Can anyone explain how a negative value for the PDOS > could occur
the PDOS is calculated using smearing. Are you by any chance using Methfessel-Paxton broadening (ngauss=1) ? it may produce negative weights. Try simple gaussian, or Marzari-Vanderbilt (cold) smearing: ngauss=0 and -1 respectively. Of course it would be nicer to use tetrahedra, but it has to be implemented (I heard that somebody had actually done this, but I have never see any code) > and also if this is actually a problem I should worry about? if the negative values are small, you shouldn't, but of cource it doesn't look nice, especially in a figure for publication! > 2. I also looked at the Energy Band Structure for CaF2 and I > am unaware of what the independent variable used for plotting > the energies from the program bands.x and plotband.x is. you mean: the x-axis of the plot? it is k, along the lines that are supplied in input, as in any respectable band structure plot Paolo -- Paolo Giannozzi e-mail: giannozz at nest.sns.it Scuola Normale Superiore Phone: +39/050-509876, Fax:-563513 Piazza dei Cavalieri 7 I-56126 Pisa, Italy
