Energy decomposition analysis in an adiabatic picture.
Yuezhi Mao1, Paul R Horn1, Martin Head-Gordon2
1Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California at Berkeley, Berkeley, CA 94720, USA. mhg@cchem.berkeley.edu.
Physical Chemistry Chemical Physics : PCCP
|February 9, 2017
Summary
Adiabatic ALMO-EDA reformulates energy decomposition analysis (EDA) to link interaction energy components to molecular properties. This method reveals how polarization and charge transfer influence molecular structure and vibrational frequencies.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Molecular Modeling
Background:
- Energy Decomposition Analysis (EDA) quantifies intermolecular interactions.
- Traditional EDA is limited to single geometries, hindering property analysis.
- The influence of EDA components on molecular structure and properties remains unclear.
Purpose of the Study:
- Reformulate Absolutely Localized Molecular Orbital (ALMO)-EDA in an adiabatic picture.
- Connect EDA energy components to molecular structure and properties.
- Investigate the role of polarization and charge transfer in intermolecular interactions.
Main Methods:
- Adiabatic ALMO-EDA using geometry optimizations on different potential energy surfaces (PESs).
- Density Functional Theory (DFT) at frozen, polarized, and fully relaxed levels.
- Application to water dimer, water-ion complexes, metallocenes, and ammonia-borane.
Main Results:
- Adiabatic ALMO-EDA provides energy contributions (frozen, polarization, charge transfer) at stationary points on PESs.
- Enables calculation of molecular properties like vibrational frequencies.
- Demonstrates how polarization and charge transfer modulate intermolecular interactions and properties.
Conclusions:
- Adiabatic ALMO-EDA is a powerful tool for understanding intermolecular interactions.
- Reveals specific contributions of polarization and charge transfer to structural preferences and frequency shifts.
- Provides deeper insights into the interplay between electronic effects and molecular properties.
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