Dear ATAT Community,
I am working on generating a Special Quasirandom Structure (SQS) for a TiAlV alloy with (90% Ti, 6% Al, 4% V) in an HCP crystal structure using the mcsqs
tool from ATAT. Despite following the documentation and an example from (Redirecting), I am encountering two issues and would appreciate your guidance.
- Uncertainty About HCP Sublattices
The article’s example (Table 1) defines two sublattices for an HCP structure, and below is my run rndstr.in
3.0 3.0 5.0 90 90 120 # Hexagonal lattice parameters (a, b, c, α, β, γ)
1 0 0 # Primitive lattice vectors
0 1 0
0 0 1
0 0 0 Ti=0.9,Al=0.06,V=0.04 # Sublattice 1
0.6666666667 0.3333333333 0.5 Ti=0.9,Al=0.06,V=0.04 # Sublattice 2
with:
corrdump Command
corrdump -l=rndstr.in -ro -noe -nop -clus -2=6 -3=5.2 -4=5.2
mcsqs
Command
mcsqs -n=100 -wr=1 -T=1 -ip=1
2- DFT Convergence Issues
After generating SQS supercells (50 and 100 atoms), I ran DFT calculations in Quantum Espresso, but the simulations did not converge.
Could someone share a working example for ternary HCP SQS (prefer TiAlV )?
Are there known best practices for corrdump/mcsqs in ternary systems?
How can I debug DFT convergence issues linked to SQS?