How can one assess the accuracy of elastic constants for 2D materials calculated via VASP and VASPKIT in the absence of literature guidance?
$\begingroup$
$\endgroup$
Add a comment
|
1 Answer
$\begingroup$
$\endgroup$
Symmetries
The elastic constants tensor obtained should reflect the symmetries of the crystal structure of the material in question. This comment article can be a helpful reference. Elastic constants that do not reflect the crystal symmetries could indicate that the DFT calculations are not converged enough, or that your strains are too large.
Convergence
This is somewhat related to the above (symmetries could be a sign of poor convergence). Generally, you could also redo calculations on finer settings (higher plane wave cutoffs, k-point sampling, etc) and check if the elastic constants change by much. It could also be a good idea to vary the maximum strain you are using for the stress-strain elastic constants calculation to check how sensitive your results are to it.
