Daniel,thanks very much for your effort..... But if it just adds the coordinates of the origin then what difference does it make??? what is the significance........i have read about the egg-box effect...but i am still in confusion....
On Tue, Jun 29, 2010 at 6:16 AM, Backlund, Daniel <[email protected]>wrote: > > 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 > > >
