Dear All,
I have two water drops on the surface and I want to distinguish them by assigning colors to them. I searched and do not exactly understand this is related to the Lammps input script file or a visualization question.
What I realized, firstly I should used dump_modify setting and then do some tools in the OVITO program …
Thanks for your comments and clarifications …
A possible post-processing workflow in OVITO would involve using any of the available Selection modifiers to select all particles belonging to one water droplet, and then applying the Assign Color modifier to color the selected particles. You would then repeat this process for the other water droplet by adding another set of Selection and Assign Color modifiers to the pipeline.
https://www.ovito.org/docs/current/reference/pipelines/modifiers/index.html#particles-modifiers
https://www.ovito.org/docs/current/reference/pipelines/modifiers/assign_color.html#particles-modifiers-assign-color
The key question to consider is whether the particles belonging to the water droplets have any per-particle property values that can be used to distinguish them (such as a type or group ID, for example). If not, what criteria would you use to define a water droplet?
Thanks @kalcher for your comment.
I grouped left drop with molecule ID assigning from 1 to 17471. I checked the software and it’s possible to color all the similar atoms.
However, I didn’t find anywhere to select the oxygen number ranging from 1 …17471 atom ID get the red color. Or molecule ID from 1 … 17471 gets the green color.
Moreover, it’s still unclear to me how is possible to define an identifier for OVITO to color the specific molecules?
Thanks for your patient and your more clarifications
In that case you can use an Expression Selection Modifier with the following boolean expression:
MoleculeIdentifier >= 1 && MoleculeIdentifier <= 17471
to select all particles that have molecule identifier values ranging between 1 and 17471.
Please also have a look at this detailed article in the OVITO manual that explains the expression syntax.
https://www.ovito.org/docs/current/reference/pipelines/modifiers/expression_select.html#particles-modifiers-expression-select
I got this error :
Unexpected token “MoleculeIdentifier” found at position 0.
Is this means my source file is not containing any information about the molecules ID? Since I checked my dump file and there were no molecules ID:
ITEM: TIMESTEP
0
ITEM: NUMBER OF ATOMS
128326
ITEM: BOX BOUNDS pp pp pp
-3.7999999999999998e+00 3.0819999999999999e+02
-2.2000000000000002e+00 2.0069999999999999e+02
-1.0199999999999999e+01 1.7069999999999999e+02
ITEM: ATOMS id type xu yu zu
104827 3 0 0 0
I didn’t see any setting for the dump_modify in Lammps to append the molecules ID.
Thanks for your time to promote our knowledge
I recommend checking out the article on the dump command in the LAMMPS manual, which provides a detailed explanation on how to export individual particle properties. For instance, you can use the custom style and include the mol attribute in the list of properties to be included in the dump file.