OVITO Forum
OVITO => Support Forum => Topic started by: majid.mgd on March 19, 2017, 09:14:32 PM

Dear all,
I have recently started working with OVITO and I’m working on nanocrystalline structures.
My current challenge is to generate a 3d crystalline structure using voronoi tessellation.
Does OVITO generate voronoi tessellations on a box of atoms just by taking the position of atoms as inputs?
What kind of process should I perform on atoms to prepare the appropriate input file for OVITO to generate (or visualize) a nanocrystalline structure with grain boundaries? (if it’s needed.)
Thanks for your answer, Majid Moghaddam

Hi Majid,
No, Ovito cannot generate atomistic models of polycrystalline microstructures for you. Please don't confuse the Voronoi analysis function (http://ovito.org/manual/particles.modifiers.voronoi_analysis.html) of Ovito with a "Voronoi crystal generator". The former constructs the Voronoi cell around each atom for characterizing the local atomic coordination, while the latter constructs the Voronoi cells for a given set of points in space (the "grain centers") and fills them with atoms on differently oriented crystal lattices.
Years ago I wrote my own Voronoi crystal generator code to produce initial starting configurations for my work on nano crystalline metals, but I think nowadays several codes have been published that provide readytouse solutions. Here is one example from a group in Germany that came to my mind:
http://www.gmp.ww.unierlangen.de/nanoSCULPT.php
You also asked for the reverse process: How to reconstruct the grain boundaries from an atomistic model of a polycrystal. Such a "grain segmentation algorithm" is being developed for Ovito, but it's not publicly available yet. I still haven't found the time to finish the work.

Hi Dr. Stukowski,
Thank you for your answer. you're right! I actually confused the Voronoi analysis function of Ovito with a voronoi crystal generator! but now thanks to your advice, I think I know where to start from. and good luck with developing the "grain segmentation algorithm".
Regards, Majid