[Pw_forum] generating kpoint

[Duy Le]

This is a simple exercise:
1. Draw the Brillouin Zone

2. Find all high symmetry points with there coordinates
for example:
Gamma (0,0,0)
E(X,Y,Z) (arbitrary)

3. If you want to calculate the dispersion (band structure) along the
line from G to E with n points, your list of k-point should be
(0., 0., 0.)
(0.+1*[(X-0)/(n-1)],0.+1*[(Y-0)/(n-1)],0.+1*[(Z-0)/(n-1)])
....
(0.+(i-1)*[(X-0)/(n-1)],0.+(i-1)*[(Y-0)/(n-1)],0.+(i-1)*[(Z-0)/(n-1)])
....
(0.+(n-1)*[(X-0)/(n-1)],0.+(n-1)*[(Y-0)/(n-1)],0.+(n-1)*[(Z-0)/(n-1)]) = (X,Y,Z)

About your second question: Yes, it is okie to use, but make sure that
you get converged total energy.

PS: Please sign your post with more information.

--------------------------------------------------
Duy Le
PhD Student
Department of Physics
University of Central Florida.

"Men don't need hand to do things"



On Fri, Jan 28, 2011 at 12:11 PM, Shaptrishi Sharma <sh.shapt at gmail.com> wrote:
> Hi QE users,
>
> I want to ask a very basis question.While doing a band structure calculation
> in quantum espresso,if I vary the lattice constant of my system (when the
> system has been repeated along X-axis),if the lattice constant along X axis
> is 'a',the reciprocal lattice value along X axis would be bx=2pi/a.Is it
> okay to divide it by desirable number of K point that we want ,suppose if I
> want 10 kpoints then in that case if I start with 0 0 0 as our 1st K_point
> followed by 2*bx/10,3*bx/10 ...etc upto 10*bx/10?Another question is about
> the K grid,is it okay to use it for different lattice by different
> parameters?
>
> Regards
>
> Shapt
>
> Pune
>
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