HRTEMFringeAnalyzer a free python module for an automated analysis of fringe pattern in transmission electron micrographs

Summary A python module ( HRTEMFringeAnalyzer ) is reported to evaluate the local crystallinity of samples from high‐resolution transmission electron microscopy images in a mostly automated fashion. The user only selects the size of a square analyser window and a step size which translates the window in the micrograph. Together they define the resolution of the results obtained. Regions where fringe patterns are visible are identified and their lattice spacing d and direction ϕ as well as the corresponding mean errors σ determined. 1 / σ dis proportional to the coherence length of the structure, whereas σ φ is a measure of how well the direction of the fringes is defined. Maps of these four indicators are computed. The performance of the program is demonstrated on two very different samples: ill‐crystalline carbon deposits on a coked Ni/LFNO (reduced LaFe 0.8 Ni 0.2 O3 ± δ ) catalyst and well‐crystallized nanoparticles of zinc doped ceria. In the latter case, the automatic segmentation of large aggregates into individual crystalline domains is achieved by ϕ maps.