I am looking at the code (siesta-2.0.2) and this specified origin is just added
to the
coordinates immediately after being read in. Your AtomicCoordinatesOrigin
should
be in the same units as AtomicCoordinatesAndAtomicSpecies.
if ( fdf_block('AtomicCoordinatesAndAtomicSpecies',iunit) )
. then
do ia = 1,nua
read(iunit,*) (xa(i,ia), i=1,3), isa(ia)
if (lOrigin) then
xa(1:3,ia) = xa(1:3,ia) + origin(1:3)
endif
enddo
Daniel J. Backlund
Texas Tech University - Physics
[email protected]
________________________________________
From: tarang mungole [[email protected]]
Sent: Tuesday, June 29, 2010 7:55 AM
To: [email protected]
Subject: [SIESTA-L] AtomicCoordinatesOrigin
Dear Siesters,
Actually I am very confused with what this AtomicCoordinatesOrigin
function does. I have created an FCC cell (it is actually a slab) with 5 layers
and one Ad-atom on the top of it.
Let us say that the height of the cubic cell(Z direction) is 5 A. What will
happen if i put the AtomicCoordinatesOrigin as follows:
%block AtomicCoordinatesOrigin
0.000 0.000 5.000
%endblock AtomicCoordinatesOrigin
or if i put it as
%block AtomicCoordinatesOrigin
0.000 0.000 6.000 # just a little more than 5 A
%endblock AtomicCoordinatesOrigin
In the manual it is written that this function applies a rigid shift. What does
this rigid shift mean? Does it just replicate the unit cell again in that
direction??can any one clarify my doubts
Thank you in advance... :)
Tarang Mungole
