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Updated: Jul 10, 2026
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Polarizable embedding cluster perturbation theory for a coupled cluster singles and doubles target state
Phillip Gustav Iuel Lunøe Dünweber1, Lars H Olsen1, Magnus Bukhave Johansen1
1Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK 2100 Copenhagen Ø, Denmark.
The Journal of Chemical Physics
|July 9, 2026
Summary
This study introduces the polarizable embedding cluster perturbation framework (PE-CP) for efficient quantum calculations. The new PE-CPS(D) method achieves high accuracy for large systems in polarizable environments.
Area of Science:
- Computational Chemistry
- Quantum Mechanics
- Theoretical Chemistry
Background:
- Accurate modeling of large quantum-mechanical systems in complex environments is computationally demanding.
- Coupled-cluster methods offer high accuracy but are often limited by computational cost.
- Polarizable embedding methods are crucial for simulating condensed-phase systems.
Purpose of the Study:
- To introduce and validate the polarizable embedding cluster perturbation framework (PE-CP).
- To develop and implement the PE-CPS(D) method for efficient, high-accuracy calculations.
- To assess the performance of PE-CPS(D) against established methods like PE-CCSD.
Main Methods:
- Derivation of working equations for the PE-CPS(D) method.
- Implementation within the Penguin program using PyFraMe and CPPE libraries.
- Utilizing a simplified iterative procedure for wave function parameters in PE-CPS(D).
Main Results:
- PE-CPS(D) allows direct evaluation of perturbative doubles contributions, reducing computational overhead.
- Numerical tests show PE-CPS(D) formally converges to PE-CCSD results.
- The method demonstrates efficiency for large quantum-mechanical systems in polarizable environments.
Conclusions:
- PE-CPS(D) offers an efficient pathway to achieve high-level coupled-cluster accuracy.
- This framework is suitable for large quantum-mechanical systems embedded in classical polarizable environments.
- The PE-CP framework provides a valuable tool for advanced computational chemistry studies.
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