Bohr / Angstrom conversion? On Thu, Feb 10, 2011 at 3:47 PM, pietro bonfa <[email protected]> wrote:
> Dear Siesta users, > > I have a problem that I wasn't able to overcome despite it has been largely > discussed in this mailing list. > The following BandLines block is from the input file that have been given > to me by Prof. Felix Yudarin: > > LatticeConstant 1.98 Ang > > %block LatticeVectors > 2.828427 0.000000 0.000000 > 0.000000 2.828427 0.000000 > 0.000000 0.000000 4.3387217 > %endblock LatticeVectors > > %block BandLines > 1 0.35355 0.000000 0.000000 X > 100 0.00000 0.000000 0.000000 \Gamma > 100 0.35355 0.353550 0.000000 M > 100 0.35355 0.000000 0.000000 X > 100 0.00000 0.000000 0.000000 \Gamma > 100 0.00000 0.000000 0.230809 R > %endblock BandLines > > > I can't figure out the calculation leading to 0.35355 for X and M point in > brillouin zone (and or course 0.230809 for R) . > > Here's how I calculate that value: > > X is [2*(pi)/a, 0, 0], where a=2.828427*LatticeConstant is real lattice > constant. > > Thus I'm expecting 2/2.828427 = 0.70710 to be the value I should put in > BandLines block. The 0.35355 value is instead about half my value. > (first brillouin zone can be found here: > http://journals.iucr.org/b/issues/2010/01/00/gw5003/gw5003fig1.jpg) > > What am I missing? > > Before concluding this email I want to thank all the people contributing to > this mailing list: I couldn't get much far if it hadn't been for all the > detailed explanation given here. > > Best regards, > Pietro >
