How to visualize grain boundary interaction with defects

Hey all,

I am fairly new to Ovito.

I have an fcc bicrystal with grain boundary constructed at the 210. The system size is 2 million atoms with two grains. I have run a primary Knock on radiation simulation with this system. I have been able to visualize the evolution of the defects (interstitials and vacancies over time). Now, I want to be able to visualize the interaction of the defects with the grain boundary. What is the best method to visualize this?

Hey,

It sounds like you are already familiar with the Wigner Seitz defect analysis.

Have you tried using OVITO’s different structure identification analyses, yet? For example, you could use the Common neighbor analysis or Polyhedral template matching modifiers in combination with the Select Type and Delete Selected modifiers to identify and delete all FCC atoms from the scene.

image

Thank you @kalcher . That worked out. I was able to visualize the interaction of the defects with the grain boundary, as shown in the attached picture. However, one thing I am wondering whether or not its possible is to visualize the Frenkel pairs(interstitials and vacancies) together with the grain boundary over time. After combing common neighbor analysis and select type, I was able to see the grain boundary and the remaing defects but when i tried adding Wigner Seitz, it’s inactive and i am unble to visualize the FPs interaction with the GB. Can you advise me?
NOTE: The different colors are just different structure types. But I want to be able to see which ones are interstitials and which ones are vacancies and how they both interact with the GB

I’m not sure what you mean by the modifier being inactive, but I believe there’s a point that needs clarification: The particles shown here represent the displaced structure, meaning the actual physical particles. These can be interstitials, but not vacancies.

Please take a look at the two working modes of the Wigner-Seitz defect analysis modifier again:
In the Sites output mode, which is likely the one you want to use, the atoms in the viewports are replaced with their ideal site positions. However, in the Atoms output mode, where the particles of the displaced configuration are kept, identifying vacancy sites isn’t possible.

Have you thought about cloning your pipeline to perform the structure identification (for your case PTM seems more suited than CNA) and Wigner Seitz defect analysis in two separate pipeline branches? That way you could show the current configuration and the identified vacancy and interstitial reference sites side by side.
https://www.ovito.org/manual/advanced_topics/clone_pipeline.html
https://www.ovito.org/manual/advanced_topics/viewport_layouts.html