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elastic constant (HELP) ZnO B3

Posted: Thu Jan 02, 2020 10:02 am
by houssem
i want to calculate elastic constant for a semiconductor compound what is the good way for this reason. I tried through elastic tutorial (Tutorespon) for calculating elastic constant of Aluminium metal, but i didn't get a good result, so any one have another method?
i have the structure parameter after optimation :
#Common input variables

#Definition of the unit cell
acell 3*4.6295 angstrom # This is equivalent to 10.61 10.61 10.61
rprim 0.0 0.5 0.5 # In tutorials 1 and 2, these primitive vectors
0.5 0.0 0.5 # (to be scaled by acell) were 1 0 0 0 1 0 0 0 1
0.5 0.5 0.0 # that is, the default.

#Definition of the atom types
ntypat 2 # There are two types of atom
znucl 30 8 # The keyword "znucl" refers to the atomic number of the
# possible type(s) of atom. The pseudopotential(s)
# mentioned in the "files" file must correspond
# to the type(s) of atom. Here, type 1 is the Aluminum,
# type 2 is the Arsenic.

#Definition of the atoms
natom 2 # There are two atoms
typat 1 2 # The first is of type 1 (Al), the second is of type 2 (As).

xred 0.0 0.0 0.0
0.25 0.25 0.25

#Gives the number of band, explicitely (do not take the default)
nband 10

#Exchange-correlation functional

ixc 11 # LDA Teter Pade parametrization

#Definition of the planewave basis set

ecut 40 # Maximal kinetic energy cut-off, in Hartree

#Definition of the k-point grid
ngkpt 4 4 4
nshiftk 4 # Use one copy of grid only (default)
shiftk 0.0 0.0 0.5 # This gives the usual fcc Monkhorst-Pack grid
0.0 0.5 0.0
0.5 0.0 0.0
0.5 0.5 0.5
So, can any one give me the input file final to calculate elastic constant

Re: elastic constant (HELP) ZnO B3

Posted: Fri Jan 10, 2020 6:06 pm
by NPike
Hello houssem,

Since you already relaxed your structure, you should start your calculation using the input file "telastic_2.in" in the tutorial.

Once you replace the system dependent variables (rprim, acell, etc. ) the input file will work for the first step of the calculation. As I am sure you noticed in the tutorial https://docs.abinit.org/tutorial/elastic/index.html there are multiple steps to this calculation.

-Nick