PyNanospacing: TEM image processing tool for strain analysis and
  visualization
Mehmet Ali Sarsil Mubashir Mansoor Mert Saracoglu Servet Timur Mustafa Urgen Onur Ergen
The diverse spectrum of material characteristics including band gap,
mechanical moduli, color, phonon and electronic density of states, along with
catalytic and surface properties are intricately intertwined with the atomic
structure and the corresponding interatomic bond-lengths. This interconnection
extends to the manifestation of interplanar spacings within a crystalline
lattice. Analysis of these interplanar spacings and the comprehension of any
deviations, whether it be lattice compression or expansion, commonly referred
to as strain, hold paramount significance in unraveling various unknowns within
the field. Transmission Electron Microscopy (TEM) is widely used to capture
atomic-scale ordering, facilitating direct investigation of interplanar
spacings. However, creating critical contour maps for visualizing and
interpreting lattice stresses in TEM images remains a challenging task. Here we
developed a Python code for TEM image processing that can handle a wide range
of materials including nanoparticles, 2D materials, pure crystals and solid
solutions. This algorithm converts local differences in interplanar spacings
into contour maps allowing for a visual representation of lattice expansion and
compression. The tool is very generic and can significantly aid in analyzing
material properties using TEM images, allowing for a more in-depth exploration
of the underlying science behind strain engineering via strain contour maps at
the atomic level.