Author Topic: lattice orientation of a complex structure  (Read 334 times)

hbluo

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lattice orientation of a complex structure
« on: March 12, 2018, 06:55:03 PM »
Dear Alex,

I am a new user of ovito. I want to visualize the lattice orientation in a muti-grain box output by Lammps. The problem is that the crystal structure is not one of those given in the documentation of PTM, i.e., hcp, fcc, bcc, etc. It has a simple hexagonal Bravais lattice with six sublattices. I am stuck by this problem now. Could you give me some suggestions to do that?

Many thanks

HBL

Alexander Stukowski

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Re: lattice orientation of a complex structure
« Reply #1 on: March 13, 2018, 09:41:58 AM »
Hi HBL,

I am afraid that isn't much that can be done. The only chance you have is if two of the six sub-lattices you mentioned would form a HCP lattice. Then you could select these atoms and use the PTM modifier on the subset of atoms only.

I would be interesting in knowing what kind of crystal structure you are dealing with. What's the name of the crystal structure (or the material)? Perhaps you have a picture of unit cell. I can discuss with Peter Larsen, the developer of PTM, whether it would be possible to add support for the structure to his identification algorithm.

-Alex

hbluo

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Re: lattice orientation of a complex structure
« Reply #2 on: March 13, 2018, 03:54:25 PM »
Hi HBL,

I am afraid that isn't much that can be done. The only chance you have is if two of the six sub-lattices you mentioned would form a HCP lattice. Then you could select these atoms and use the PTM modifier on the subset of atoms only.

I would be interesting in knowing what kind of crystal structure you are dealing with. What's the name of the crystal structure (or the material)? Perhaps you have a picture of unit cell. I can discuss with Peter Larsen, the developer of PTM, whether it would be possible to add support for the structure to his identification algorithm.

-Alex

Dear Alex,

Thank you for your reply. It is a CaCu5-type structure as attached. I am afraid that choosing part of the sublattices does not work either. To my understanding, one sublattice is enough in principle to determine the orientation, so why does not the identification use the 14 Bravais lattices instead of the crystal structure, since there will be too many crystal structures to consider? The same question exists for other analysis algorithm that applies only to bcc, fcc, hcp etc. Are there any extended methods or custom way to analyze complex structures (I am going to analyze the deformation of this structure)?

HBL
« Last Edit: March 13, 2018, 04:03:58 PM by hbluo »