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Multireference calculations for ring inversion and double bond shifting in cyclooctatetraene
1Freie Universität Berlin, Institut für Chemie und Biochemie, Takustr. 3, 14195 Berlin, Germany. axel.schild@fu-berlin.de
Journal of Computational Chemistry
|March 20, 2013
Summary
Accurate multireference calculations are essential for understanding cyclooctatetraene
Area of Science:
- Computational chemistry
- Quantum chemistry
- Molecular modeling
Background:
- Cyclooctatetraene undergoes complex structural transformations.
- Understanding these transformations requires accurate theoretical methods.
- Previous studies may not have fully captured the electronic correlation effects.
Purpose of the Study:
- To characterize the ring inversion and double bond shifting in cyclooctatetraene.
- To evaluate the accuracy of different multireference methods for these processes.
- To identify computationally efficient methods for simulating cyclooctatetraene dynamics.
Main Methods:
- Multireference configuration interaction (MRCI)
- Third-order perturbation theory (MP3)
- Complete active space self-consistent field (CASSCF) calculations
- High-level quantum chemical calculations
Main Results:
- Accurate treatment of dynamical correlation is crucial for barrier height calculations.
- MRCI and MP3 provide accurate barrier heights.
- CASSCF offers a surprisingly good description of the processes.
- CASSCF is a computationally cheaper alternative.
Conclusions:
- Dynamical correlation is key for accurate cyclooctatetraene energetics.
- CASSCF provides a viable and efficient method for dynamics simulations.
- This work offers insights into the computational chemistry of polycyclic hydrocarbons.
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