Sensitivity of quantitative symmetry measurement algorithms for convergent beam electron diffraction technique.

We investigate the sensitivity of symmetry quantification algorithms based on the profile R-factor (R) and the normalized cross-correlation (NCC) coefficient (γ). A DM (Digital Micrograph) script embedded in the Gatan digital microscopy software is used to develop the symmetry quantification program. Using the Bloch method, a variety of CBED patterns are simulated and used to investigate the sensitivity of symmetry quantification algorithms. The quantification results show that two symmetry quantification coefficients are significantly sensitive to structural changes even for small strain values of < 1%.