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Perturbed atoms in molecules and solids: The PATMOS model
1Centre for Theoretical and Computational Chemistry (CTCC), Department of Chemistry, University of Tromso̸, N-9037 Tromso̸, Norway.
The Journal of Chemical Physics
|September 14, 2013
Summary
A new computational method, the perturbed atoms in molecules and solids model, offers accurate electronic-structure studies. This approach refines unrestricted Hartree Fock (UHF) calculations for molecules and solids.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Materials Science
Background:
- Accurate electronic-structure calculations are crucial for understanding molecular and solid-state properties.
- Existing methods may face limitations in accuracy or computational cost for complex systems.
Purpose of the Study:
- To introduce a novel computational method for electronic-structure studies.
- To develop a model based on the concept of perturbed atoms within molecules and solids.
Main Methods:
- The perturbed atoms in molecules and solids model utilizes unrestricted Hartree Fock (UHF) as its basic approximation.
- Unrestricted Hartree Fock (UHF) orbitals are localized using the Edmiston-Ruedenberg procedure.
- Energy corrections are calculated via an energy incremental scheme, incorporating modified geminal approaches for electron correlation.
Main Results:
- The perturbed atom concept is defined by minimizing the sum of intra-atomic UHF energies.
- Test calculations on N2, Li2, and hydrogen atom arrays demonstrate the method's applicability.
- Further illustrations on H2, CH4, and C6H6 elucidate the character of perturbed atoms.
Conclusions:
- The perturbed atoms in molecules and solids model presents a viable new approach for electronic-structure investigations.
- The method shows promise for accurate calculations on various molecular and solid-state systems.
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