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Canonically consistent quantum master equation for proton-transfer reactions
Zahra Sartipi1, Richard Gundermann2, Janet Anders1,3
1University of Potsdam, Institute of Physics and Astronomy, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany.
The Journal of Chemical Physics
|August 4, 2026
Summary
The canonically consistent quantum master equation (CCQME) accurately models quantum system-bath dynamics for intramolecular proton transfer in thioacetylacetone. CCQME shows better agreement with hierarchical equations of motion (HEOM) than Redfield theory, especially at stronger couplings.
Area of Science:
- Quantum Chemistry
- Theoretical Chemistry
- Chemical Physics
Background:
- System-bath dynamics are crucial for understanding chemical reactions.
- Intramolecular proton transfer is a fundamental process in chemistry.
- Accurate theoretical methods are needed to model complex quantum dynamics.
Purpose of the Study:
- To evaluate the canonically consistent quantum master equation (CCQME) for system-bath dynamics.
- To model intramolecular proton transfer in thioacetylacetone (TAA).
- To compare CCQME with hierarchical equations of motion (HEOM) and Redfield theory.
Main Methods:
- Modeling TAA as an N-level quantum system coupled to a harmonic bath.
- Utilizing the CCQME method.
- Benchmarking against numerically exact HEOM and secularized Redfield theory.
Main Results:
- CCQME population dynamics show good agreement with HEOM for moderate system-bath couplings.
- Redfield theory deviates significantly from HEOM as coupling strength increases.
- Non-secular CCQME calculations highlight limitations for coherence-sensitive observables.
Conclusions:
- CCQME provides a reliable method for studying system-bath dynamics in chemical processes.
- CCQME offers an improvement over Redfield theory for TAA proton transfer.
- Higher-order treatments are necessary for accurately capturing coherence effects.
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