Dear SIESTA users, I am trying to do the calculation of piezoelectric coefficients for bulk ZnO with a unit cell consisting of 4 atoms. Coefficient (d33) is calculated as the slope of polarization vs strain curve. Strain is dimensionless and therefore the units of d33 is same as that of polarization.
In SIESTA output, the polarization is expressed in Debye units (1 Debye = 3.33 X 10e-30 C-m). To convert it to C/m^2 (standard unit used for d33), I am diving by the volume of the unit cell. Is that correct or am I missing something? Thanks in advance. Ravi
