The finite difference and the density functional
perturbation theory based piezoelectric property calculation methods are
applied to the novel two dimensional hexagonal materials named as group II-VI
monolayers and transition metal dichalcogenides for the purposes of comparison.
The clamped- and relaxed- ion coefficients have been calculated separately to test
the accuracy of both methods on electronic and ionic piezoelectric response contributions.
While there is no significant difference between the clamped-ion piezoelectric
coefficients calculated with these two methods, a notable difference between
the values for relaxed-ion piezoelectric coefficients are determined. Considering
the results of the density functional perturbation theory given in the previous
applications, it has been determined that the consistency of the finite difference
method in the ionic contribution calculation do not provide reliable results for
some 2D materials. We have predicted that the atomic relaxation for different
strain values is not adequate to achieve accurate results for ionic
contribution of piezoelectric coefficient. However, on the contrary to the explicit difference in the coefficients calculated
with two different approaches, our results clearly show that the piezoelectric
potentials of the considered materials can be determined accurately and
reliably by both methods.
Subjects | Engineering |
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Journal Section | Articles |
Authors | |
Publication Date | September 30, 2017 |
Published in Issue | Year 2017 Volume: 18 Issue: 3 |