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Updated: Sep 30, 2025
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Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
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Systematic QM Region Construction in QM/MM Calculations Based on Uncertainty Quantification.
Felix Brandt1, Christoph R Jacob1
1Institute of Physical and Theoretical Chemistry, Technische Universität Braunschweig, Gaußstr. 17, 38106 Braunschweig, Germany.
Journal of Chemical Theory and Computation
|March 10, 2022
Summary
Quantifying uncertainties in QM/MM calculations is crucial. A point charge variation analysis (PCVA) helps optimize the quantum mechanics (QM) region for accurate enzymatic reaction energies.
Area of Science:
- Computational chemistry
- Biophysical chemistry
- Quantum mechanics/molecular mechanics (QM/MM)
Background:
- QM/MM studies are vital for enzymatic reactions but face uncertainties.
- Selecting the quantum mechanics (QM) region is critical for accuracy.
- Distance-based QM region selection is often insufficient.
Purpose of the Study:
- To quantify uncertainties in QM/MM calculations.
- To assess the sensitivity of QM/MM reaction energies to molecular mechanics (MM) point charges.
- To develop a protocol for systematic QM region construction.
Main Methods:
- Point Charge Variation Analysis (PCVA) to assess QM/MM reaction energy sensitivity.
- Systematic protocol for QM region construction.
- Application to catechol O-methyltransferase.
Main Results:
- PCVA effectively judges QM/MM reaction energy accuracy.
- A protocol was devised to minimize QM/MM uncertainty.
- The PCVA-based scheme is computationally efficient.
Conclusions:
- PCVA offers a reliable method for QM region construction in QM/MM studies.
- Uncertainty quantification is promising for computational chemistry.
- The developed scheme aids in accurate enzymatic reaction modeling.
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