[xcrysden] How to choose special direction with xcryden in WIEN2k

[Tone Kokalj]

On Fri, 2005-07-22 at 13:03 -0700, Sherif Yehia wrote:
> Dear Sir
> 
>    I working on a hexagonal system and I hope to plot
> the calculated  band structure in  the following
> special directions (Using Wien2k) 
>    
>   1-A(001)          2-Delta(0 0 1/2)   3-GAMMA (0 0 0)
>   4-Sigma(1/3 0 0)  5-Sigma(2/3 0 0)   6-M(100)
>   7-U(1 0 1/2)      8-L( 1 0 1)

The problem is the "unit" of the k-points; xcrysden prints the k-points
in terms of primitive reciprocal lattice vectors. WIEN2k does not use
these "units" for some Bravais lattices. 

In terms of primitive reciprocal lattice vectors a few of the points
above would be:

A (0,0,1/2)
M (1/2, 0, 0)
L (1/2, 0, 1/2)

These is probably what the xcrysden prints on the window. Of course,
when you save the WIEN2k formated klist file, these points are converted
to the "units" WIEN2k uses. Compare for example, the coordinates printed
on the window and saved on the wien2k formated file.

Regards, Tone