The ABINIT Users Mailing List ( CLOSED )

["Aldo Humberto Romero" <aromero@qro.cinvestav.mx>]

Dear Thanusit

> 1. Regarding the "q point grids", does this refer to the input parameters
> "ngqpt"in the input file of the "anaddb" program?(as listed below)

it refers to the number of dinamical matrices to be calculated. The
parameter that appears in the anaddb only depends omn thenumber
of q points (meaning the q-grid) you have used. Therefore
the convergence referst to that

>
> ------Part of trf2_4.in----------
> !Wavevector grid number 1 (coarse grid, from DDB)
>   brav          2         ! Bravais Lattice : 1-S.C., 2-F.C., 3-B.C., 
> 4-Hex.)
>   ngqpt   4  4        4   ! Monkhorst-Pack indices
>   nqshft  1       ! number of q-points in repeated basic q-cell
>   q1shft  3*0.0
> ------------------------------------------------------
>
> 2. What are the calculated parameters we have to look at in these
> convergence
> studies? Is it enough just to examine the convergence of phonon frequency?

Gamma will be Ok from my experience.. comparing with experimental
values.. depending on your different parameters you can
get as good at 1% but 5% ismore usual..
>
> 3. Is there any example on the phonon dos calculation by "anaddb"?
>

I am sure there are in the tests directory... it is really
something nice from anaddb, where you can calculated many other properties
besides deh phonon band structure. Remember that thanks to the
interpolation scheme implemented in Abinit, you can obtain a more
dense  phonon band structure.

regards


-aldo.

> All suggestions and comments are appreciated.
>
> Regards,
> Thanusit Burinprakhon
>
> Physics department,
> Khon-Kaen university, Thailand.
>


---------------------------------------------------
Prof. Aldo Humberto Romero
CINVESTAV-Unidad Queretaro
Libramiento Norponiente 2000
CP 76230, Queretaro, QRO, Mexico
tel: 442 211 9909
fax: 442 211 9938
email: aromero@qro.cinvestav.mx
       aldorome@gmail.com
www: qro.cinvestav.mx/~aromero