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The CCSD(T) complete basis set limit for Ne revisited.
Ericka C Barnes1, George A Petersson, David Feller
1Hall-Atwater Laboratories of Chemistry, Wesleyan University, Middletown, Connecticut 06459-0180, USA.
The Journal of Chemical Physics
|November 26, 2008
Summary
Accurate Coupled Cluster calculations refine the energy limit for neon atoms. This improved benchmark aids in calibrating less precise computational methods for atomic and molecular studies.
Area of Science:
- Quantum Chemistry
- Atomic Physics
- Computational Chemistry
Background:
- Accurate theoretical calculations are crucial for understanding atomic properties.
- Previous estimates of the Coupled Cluster Singles Doubles with Perturbative Triples (CCSD(T)) energy limit for neon required refinement.
Purpose of the Study:
- To refine the coupled cluster energy limit for the neon atom.
- To establish a highly accurate benchmark for computational chemistry.
Main Methods:
- Re-examination of basis set convergence for various components of the valence CCSD(T) energy.
- Inclusion of self-consistent field (SCF), MP2-alphabeta, MP2-alphaalpha, CCSD-MP2, and (T) contributions.
Main Results:
- A complete basis set limit for the neon atom's CCSD(T) energy was determined to be -128.869 236 ± 0.000 02 hartree.
- This value represents a significant refinement over previous estimates.
Conclusions:
- The refined energy limit provides a more accurate benchmark for theoretical calculations.
- This benchmark can be used to calibrate and improve approximate computational methods for neon and similar atomic systems.
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