VASP Computing Generalized Stacking Fault Energy of Au

From Micro and Nano Mechanics Group
Jump to navigation Jump to search

VASP: Genearlized Stacking Fault Energy of Au


Input files

Here are the basic input files required for VASP calculation. Some of the files need to be changed since we need to perform a large number of calculations.

INCAR

System = fcc Au
LWAVE = .FALSE.
ENCUT  =  400
ISMEAR  = 1
SIGMA = 0.1
ISIF = 2

KPOINTS

test convergence
0        0 = automatic generation of k-points
Monkhorst
7 7 11
0 0 0

POSCAR

POSCAR for FCC Au (created manually)
4.0605
 1.22474487139159 0                0
 0                1.73205080756888 0
 0                0                0.70710678118655
6
Cartesian  (real coordinates r)
 0                0                0
 0.40824829046386 0.57735026918963 0
 0.81649658092773 1.15470053837925 0
 0.61237243569579 0                0.35355339059327
 1.02062072615966 0.57735026918963 0.35355339059327
 0.20412414523193 1.15470053837925 0.35355339059327

You also need to put the LDA pseudopotential file as POTCAR in this directory.

Results

Perfect crystal

The following table shows energy convergence with k-points. (Reference value from Au_bulk calculation: E = -4.39 eV/atom.)

KPOINTS E (eV/atom) optimal number of CPUs
3x3x3 -4.4735468
5x5x5 -4.4121563
7x7x7 -4.4043722
7x7x11 -4.3981093 16
7x5x13

Unrelaxed stacking fault energy

We now fix KPOINTS at 7x7x11, for which the energy of perfect crystal is E = ???? (eV/atom).

Unrelaxed stacking fault energy
E1 (raw data) ?? (eV)
E0 (perfect crystal) ?? (eV/atom)
Ex (excess) = (E1-E0*6) ?? (eV)
Area ?? (angstrom^2)
Esf (unrelaxed) = Ex / Area ?? (eV/angstrom^2) =  ?? (mJ/m^2)


Relaxed stacking fault energy

We now fix KPOINTS at 7x7x11, for which the energy of perfect crystal is E = ???? (eV/atom).

Unrelaxed stacking fault energy
E1 (raw data) ?? (eV)
E0 (perfect crystal) ?? (eV/atom)
Ex (excess) = (E1-E0*6) ?? (eV)
Area ?? (angstrom^2)
Esf (unrelaxed) = Ex / Area ?? (eV/angstrom^2) =  ?? (mJ/m^2)


Unrelaxed generalized stacking fault energy

We now fix KPOINTS at 7x7x11, for which the energy of perfect crystal is E = ???? (eV/atom).

Unrelaxed stacking fault energy
E1 (raw data) ?? (eV)
E0 (perfect crystal) ?? (eV/atom)
Ex (excess) = (E1-E0*6) ?? (eV)
Area ?? (angstrom^2)
Esf (unrelaxed) = Ex / Area ?? (eV/angstrom^2) =  ?? (mJ/m^2)


Relaxed generalized stacking fault energy

We now fix KPOINTS at 7x7x11, for which the energy of perfect crystal is E = ???? (eV/atom).

Unrelaxed stacking fault energy
E1 (raw data) ?? (eV)
E0 (perfect crystal) ?? (eV/atom)
Ex (excess) = (E1-E0*6) ?? (eV)
Area ?? (angstrom^2)
Esf (unrelaxed) = Ex / Area ?? (eV/angstrom^2) =  ?? (mJ/m^2)
Retrieved from "http://micro.stanford.edu/mediawiki/index.php?title=VASP_Computing_Generalized_Stacking_Fault_Energy_of_Au&oldid=2329"