[Wien] FSGEN

[Peter Blaha]

>  I still have some questions about FSGEN. Take TiC as an example. I choose
> the plane Gamma-X-XP-K-Gamma and 40 points in both kx and ky directions.

This is the (001) plane and thus the corner of that plane are
Gamma (0,0,0), X (1,0,0), X'(0,1,0) and K (1,1,0)

Thus the "lenght of the sides of this square is simply 2pi/a.

The k-mesh generated in fort.2 covers only one triangle of that square
(thus you need flip and/or inverse!!!) and looks (for 6 points only):
         1    0    0    0    6 1.00-7.00 1.50        4   3
         2    1    0    0    6 1.00
         3    2    0    0    6 1.00
         4    3    0    0    6 1.00
         5    4    0    0    6 1.00
         6    5    0    0    6 1.00
         7    6    0    0    6 1.00
         8    1    1    0    6 1.00
         9    2    1    0    6 1.00
        10    3    1    0    6 1.00
        11    4    1    0    6 1.00
        12    5    1    0    6 1.00
        13    6    1    0    6 1.00
        14    2    2    0    6 1.00
        15    3    2    0    6 1.00
        16    4    2    0    6 1.00
        17    5    2    0    6 1.00
        18    6    2    0    6 1.00
        19    3    3    0    6 1.00
        20    4    3    0    6 1.00
        21    5    3    0    6 1.00
        22    6    3    0    6 1.00
        23    4    4    0    6 1.00
        24    5    4    0    6 1.00
        25    6    4    0    6 1.00
        26    5    5    0    6 1.00
        27    6    5    0    6 1.00
        28    6    6    0    6 1.00

This does NOT correspond to what you included in spagh_ene in your mails.
I guess you still used the scf kmesh ??

> (1) UG says (page 128) "Run spaghetti with input-options such that it
> prints the bands which intersect EF to case.spaghetti.ene (line 6, see
> section.8.3). I followed the instruction in sec. 8.3 and 7.5 but it doesn't
> make any chnage in case.spaghetti.ene. What input-options should be used?

At the bottom there is a line saying we put bands x-y to *_ene file.
It is your task to find out which bands cross EF and put it into
case.insp.
For TiC it is definitely not band 1-5 (These are the Ti 3s,3p and C 2s
bands), but then it might get interesting. Just check your bandstructure
picture.

Regards

                                      P.Blaha
--------------------------------------------------------------------------
Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
--------------------------------------------------------------------------