[ase-users] Si(001)surface

[sudip chakraborty]

hi ase users

bellow is the Si surface cut from bulk..but i have basic
crystallographic question and that is, hwo to cut means what are the
values of a,b,c if we want to make Si(100) surface?and how to
determine that??will be very helpful to me if I will get the
answer....

##########################################################
from ase import Atoms
from ase.visualize import view
from ase.io import write, read
from ase.data.molecules import *
from ase.lattice.spacegroup import crystal
from ase.lattice.spacegroup.crystal import *
from ase.utils.geometry import *
from ase.lattice.surface import *

a = 5.431

slab = crystal('Si', [(0,0,0)], size=(2,2,2), spacegroup=227,
cellpar=[a, a, a, 90, 90, 90])

slab.center(vacuum=15, axis=2)

slab = cut(slab, a=[0,0,1], b=[1,-1,0], c=[1,1,0])

write ('slab.xyz', slab)
slab_from_file = read ('slab.xyz')

view (slab)
######################################################################

Regards
SC