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The choice of internal coordinates in complex chemical systems
Károly Németh1, Matt Challacombe, Michel Van Veenendaal
1Department of Physics, Northern Illinois University, DeKalb, Illinois 60115, USA. nemeth@anl.gov
Journal of Computational Chemistry
|January 21, 2010
Summary
Choosing internal coordinates is crucial for complex chemical systems. This study introduces a robust algorithm for automatically selecting appropriate internal coordinates, improving geometry manipulations in molecular dynamics and optimizations.
Area of Science:
- Computational Chemistry
- Chemical Physics
Background:
- Cartesian coordinates are traditionally used for molecular geometry manipulations.
- Internal coordinates offer advantages for certain chemical system analyses.
- A need exists for automated selection of internal coordinates.
Purpose of the Study:
- To present considerations for selecting appropriate internal coordinates in complex chemical systems.
- To highlight the importance of automated internal coordinate recognition.
- To introduce a robust algorithm for this purpose.
Main Methods:
- Development of a novel algorithm for internal coordinate determination.
- Testing the algorithm across diverse chemical systems and atomic arrangements.
- Comparison with traditional Cartesian coordinate approaches.
Main Results:
- The algorithm demonstrates robust and rapid identification of suitable internal coordinates.
- Successful application across a wide range of atomic configurations.
- Facilitates the extension of internal coordinate algorithms to new fields.
Conclusions:
- Automated internal coordinate selection is fundamental for advancing computational chemistry.
- The presented algorithm offers a significant improvement over manual or Cartesian methods.
- Enables broader application of internal coordinate-based methods in molecular modeling.
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