Quantifying shapes of nanoparticles using modified circularity and ellipticity measures

We propose using a new circularity measure, and an ellipticity measure. Observing an example of hematite (α-Fe2O3) nanoparticles, we compared and discussed a new circularity measure, with a standard measure. It has been shown that using the new measure gives better results when working with low-quality images or with low-resolution images. Using the same images modified ellipticity measure has also been discussed. We have analyzed the problems arising from computing the elongation of a shape. We have shown that the standard approach to compute elongation is not appropriate for some particles. We presented the application of the modified approach to solve this problem.