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[jej7x@xenon.cchem.berkeley.edu]

Hi, I'm pretty new to abinit, and I'm trying to look at the 111 surface of 
Ag.  To do that, I'm trying to follow my way through the
tutorials, and so I'm starting with tutorial #4, and adapting that to the 111 
surface.  As a first step, I tried adjusting rprim so that
one of my axes will be along the 111 direction, and the other 2 would stay in 
the 111 plane.  So I created the following input file.  When
I use this, everything converges with no warnings, but the ions end up at the 
following coordinates
xred
0.0 0.0 -.036307
2/3 1/3 0.277767859
0.0  1.0 5.91873013
These changes are on the order of -.2 to -.4 bohr in the 111 direction


However, if I change my  coordinates back to the typical fcc lattice 
(rprim = 0.5 0.5 0
         0.5 0.0 0.5
          0.0 0.5 0.5
natom 1
xred 0.0 0.0 0.0)
I get no ion movement, and it says that at MD/Broyden step 0, all gradients 
converged.   It also gives no xred, xcart, or xangst in the
output file (I assume b/c they didn't change). Did I just redefine the FCC 
crystal using a poor (or even plain outright wrong) basis?
Help would be awesome.  
--James

--------------------------------------------------------------------------
#Bulk Aluminum FCC crystal (I hope)

occopt 4
tsmear 0.04
nband 8
kptopt 1
ngkpt 6 6 6
nshiftk 1
shiftk 0.5 0.5 0.5


 #Definition of the unit cell
acell 3*7.50559090E+00   # Lattice parameters of bulk aluminum
rprim  0.5 0.0  -0.5     # These values will define a cell with three atoms, 
       -0.5  0.5  0.0     # non-primitive, with a different orientation
       1.0  1.0  1.0     # than the primitive cell.
chkprim 0
ntypat 1
znucl 13

#Definition of the atoms
natom 3
typat 3*1
xred 0.0 0.0 0.0
      2/3 1/3 1/3
     0.0   1.0 0.5

#Convergence Criteria
ionmov 2
tolmfx 1d-4
ntime 15
getwfk  -1
nstep 10
toldfe 1d-6
-------------------------------------------------------------------------------