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Knowles Partitioning at the Multireference Level
Ágnes Szabados1, András Gombás1, Péter R Surján1
1Laboratory of Theoretical Chemistry, Institute of Chemistry, Faculty of Science, ELTE Eötvös Loránd University, H-1518 Budapest 112, Budapest P.O.B. 32, Hungary.
The Journal of Physical Chemistry. A
|October 11, 2024
Summary
This study introduces a multireference extension of a partitioning method to investigate electronic systems with moderate electron correlation. The approach utilizes multiconfiguration perturbation theory for enhanced computational accuracy.
Area of Science:
- Quantum Chemistry
- Computational Physics
- Theoretical Chemistry
Background:
- Accurate electronic structure calculations are crucial for understanding chemical phenomena.
- Existing methods may struggle with systems exhibiting medium levels of electron correlation.
- Recent advancements in partitioning techniques offer new avenues for computational efficiency.
Purpose of the Study:
- To generalize a recently developed partitioning method for multireference electronic systems.
- To enable the study of electronic systems at a medium level of correlation.
- To apply the multiconfiguration perturbation theory (MCPT) framework.
Main Methods:
- Generalization of Knowles' partitioning method.
- Application of the multiconfiguration perturbation theory (MCPT) formalism.
- Development of a multireference computational approach.
Main Results:
- A novel multireference generalization of a partitioning technique is established.
- The developed method is suitable for studying electronic systems with medium correlation.
- Successful integration within the MCPT framework.
Conclusions:
- The presented multireference partitioning method offers a viable approach for medium-correlation systems.
- This work extends the applicability of partitioning techniques in quantum chemistry.
- The MCPT framework provides a robust foundation for these advanced calculations.
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