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Automated assignment of graph-set descriptors for crystallographically symmetric molecules
1Cambridge Crystallographic Data Centre, England. motherwell@ccdc.cam.ac.uk
Summary
New algorithms systematically assign graph-set notation for intermolecular networks, even in molecules with internal crystallographic symmetry. This ensures consistent network analysis for symmetric molecules using the RPLUTO program.
Area of Science:
- Crystallography
- Supramolecular Chemistry
- Chemical Informatics
Background:
- Intermolecular networks are crucial for crystal engineering and material properties.
- Automatic assignment of graph-set notation aids in understanding these networks.
- Existing methods struggle with molecules possessing internal crystallographic symmetry.
Purpose of the Study:
- To extend graph-set notation algorithms for intermolecular networks to include molecules with internal crystallographic symmetry.
- To develop a systematic and consistent method for analyzing networks with symmetric molecules.
- To implement these methodologies in a user-friendly software program.
Main Methods:
- Extension of existing graph-set notation algorithms to handle internal crystallographic symmetry.
- Development of algorithms for patterns up to the second level of symmetry.
- Implementation of the extended methodologies within the RPLUTO software.
Main Results:
- Successful extension of graph-set notation algorithms to symmetric molecules.
- Demonstration of systematic and consistent assignments for complex intermolecular networks.
- Validation of the RPLUTO program with diverse examples of hydrogen-bonded and other networks.
Conclusions:
- The developed algorithms provide a robust method for analyzing intermolecular networks in crystals with symmetric molecules.
- The RPLUTO program offers a valuable tool for researchers in crystallography and supramolecular chemistry.
- This advancement facilitates a deeper understanding of structure-property relationships in crystalline materials.
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