Author Topic: RandomAlSubstitution_13X  (Read 49 times)

rshukre

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RandomAlSubstitution_13X
« on: September 26, 2021, 12:58:13 AM »
Hello,

I have a question regarding RandomAlSubstitution to modify the Si/Al ratio in zeolite 13X. In the manual, it is written that the 'Substitute' command is useful to have the same structure, whereas the 'RandomlySubstitute' command may not keep the same space group. I want to substitute 10 Al atoms by 10 Si atoms in the framework. How many 'Substitute' commands do I need to consider in the input file, so as to keep the space group in the fd-3, with 96 elements ? How do I check if the same space group is followed at the end of simulation.

Regards,
Rajasi


David Dubbeldam

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Re: RandomAlSubstitution_13X
« Reply #1 on: September 27, 2021, 07:22:09 PM »
Usually, the experimental structure is an average over all unit cells, and that is then described by a space group.
In simulation, you need to define all atoms, so it is unlikely that the space group is the same (for structures with partial occupancies).
So, just convert to P1 and do the substitution.

rshukre

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Re: RandomAlSubstitution_13X
« Reply #2 on: September 28, 2021, 06:45:14 PM »
Thank you.