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Published on: May 27, 2020
Interaction-induced electric properties and cooperative effects in model systems
Angelika Baranowska1, Agnieszka Zawada, Berta Fernández
1Department of Physical Chemistry, Faculty of Chemistry, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
Physical Chemistry Chemical Physics : PCCP
|January 13, 2010
Summary
This study analyzes electric dipole properties and interaction energies in formaldehyde-hydrogen fluoride complexes. New LPol basis sets provide accurate results, revealing that many-body effects are crucial for predicting properties in longer chains.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Molecular Interactions
Background:
- Understanding electric dipole properties of molecular complexes is vital for predicting their behavior in external fields.
- Formaldehyde-hydrogen fluoride (HCHO(HF)n) complexes serve as model systems for studying intermolecular interactions and cooperative effects.
Purpose of the Study:
- To perform a detailed analysis of interaction-induced linear and non-linear axial static electric dipole properties and interaction energies of HCHO(HF)n complexes (n=1, 2).
- To evaluate the performance of various computational methods and basis sets, particularly the novel LPol sets, for calculating these properties.
- To investigate cooperative effects and many-body contributions to electric properties in HCHO(HF)n complexes up to n=9.
Main Methods:
- High-level ab initio calculations using Hartree-Fock Self-Consistent Field (HF SCF), Møller-Plesset perturbation theory (MP2), Coupled Cluster Singles and Doubles (CCSD), and CCSD(T) approximations.
- Employment of diverse basis sets including Dunning's correlation-consistent sets, Jensen's polarization-consistent sets, and the LPol sets (LPol-ds, LPol-dl, LPol-fl).
- Many-body analysis to dissect contributions from two-body and higher-order interactions.
Main Results:
- The smallest LPol basis sets (LPol-ds, LPol-dl) achieve accuracy comparable to the large aug-cc-pVQZ set for interaction-induced axial static electric dipole properties.
- Estimated induced electric properties and interaction energies for HCHO(HF)n complexes (n=1-9) using LPol sets.
- Many-body analysis indicates that two-body contributions are insufficient for longer chains (n≥4), with many-body terms becoming dominant for induced first hyperpolarizability.
Conclusions:
- The LPol basis sets offer an efficient and accurate alternative for calculating electric dipole properties of molecular complexes.
- Cooperative and many-body effects significantly influence the electric properties of HCHO(HF)n complexes as the chain length increases.
- Accurate prediction of properties in extended systems requires the inclusion of terms beyond two-body interactions.
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