[Pw_forum] question about LDOS calculation within boxes using pp.x

[HABIBI Parwana]

Dear QE users,

I have been trying to use pp.x on a Cr(001) slab, and I would like to calculate PDOS in a box above de surface.
As a matter of fact, I would like to see the decrease of the wavefunctions in the vacuum, by analysing the PDOS in boxes at different heights.
After a calculation on small boxes, I would like to have, now, an average type box, on the whole surface, so let's say a pavement-like box.

After a pp.x regular PDOS calculation, I have noticed that the segmentation along x and y direction is 30, I thought that regarding this information, I could take a box with a width of 30 on x and y direction for another pp.x calculation with the boxes to get the big box I need.

Hence, pp.x generates a .xsf file for visualizing the boxes. When I would calculate it with a small box (width=2 on x and y directions, ie irmin(1)=1, irmax(1)=3 in the pp.x input file), I could see the box with xcrysden. However, using the big values (30) for my boxes boundaries, I cannot visualize them. But I still get a result about ldos in the boxes.

My questions are the following : how can I be sure that the ldos calculation are actually done within my big boxes boundaries? Is it correct to use that big segmentation in the first place?

I've included the pp.x box input.

Thank you,


Parwana Habibi
PhD student
CEA-Saclay
DSM/IRAMIS/SPCSI/LNOSC
France
 




-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20110728/4a03542d/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: box_up.in
Type: application/octet-stream
Size: 1571 bytes
Desc: box_up.in
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20110728/4a03542d/attachment.obj>