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The Ground State Electronic Energy of Benzene
Janus J Eriksen1, Tyler A Anderson2, J Emiliano Deustua3
1School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
The Journal of Physical Chemistry Letters
|October 6, 2020
Summary
This study assessed high-accuracy electronic structure methods for benzene's ground-state energy. While methods agreed on the correlation energy, significant deviations highlight challenges in scaling accurate methods to larger systems.
Area of Science:
- Quantum chemistry
- Computational physics
- Materials science
Background:
- Accurate determination of molecular energies is crucial for understanding chemical phenomena.
- Full configuration interaction (FCI) provides exact energies but is computationally intractable for large systems.
- Wave function-based correlation methods offer approximations to FCI.
Purpose of the Study:
- To evaluate and compare various high-level wave function-based methods for calculating the FCI ground-state energy of benzene.
- To assess the accuracy and scalability of modern electronic structure methods.
- To provide a benchmark for future computational chemistry studies.
Main Methods:
- Blind challenge format involving multiple international research groups.
- Application of diverse wave function-based correlation methods.
- Calculation of frozen-core, FCI ground-state energy for benzene using a double-ζ basis set.
Main Results:
- Qualitative agreement among methods regarding the final correlation energy, with estimates around -863 mEH.
- A considerable root-mean-square deviation of 1.3 mEH between the studied methods.
- Demonstration of challenges in extending accurate correlation methods to larger molecular systems.
Conclusions:
- Current state-of-the-art methods show room for improvement in accuracy and scalability.
- The study provides a valuable community resource for benchmarking and calibration of electronic structure methods.
- Discrepancies highlight the ongoing need for developing more reliable and efficient computational approaches.
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