Basis set representation of the electron density at an atomic nucleus
Remigius Mastalerz1, Per-Olof Widmark, Björn Olof Roos
1Laboratorium für Physikalische Chemie, ETH Zurich, Wolfgang-Pauli-Str. 10, CH-8093 Zurich, Switzerland.
The Journal of Chemical Physics
|October 19, 2010
Summary
This study details basis set convergence for calculating relativistic electron densities near nuclei. It explores Gauss-type basis sets and contraction schemes for accurate electronic structure calculations.
Area of Science:
- Computational chemistry
- Quantum chemistry
- Relativistic quantum mechanics
Background:
- Accurate calculation of relativistic electron densities is crucial for understanding chemical properties and bonding.
- Basis set convergence is a key challenge in relativistic electronic structure theory.
- Finite-sized nuclei effects require specialized computational approaches.
Purpose of the Study:
- To investigate basis set convergence for relativistic electron densities at finite-sized nuclei.
- To develop and evaluate Gauss-type basis sets for these calculations.
- To assess the impact of various computational factors on accuracy.
Main Methods:
- Development of Gauss-type basis sets.
- Analysis of different basis set contraction schemes.
- Picture-change corrected calculations using the Douglas-Kroll-Hess Hamiltonian.
- Investigation of electron correlation effects.
- Assessment of numerical integration accuracy in density functional theory (DFT).
- Convergence studies with respect to Douglas-Kroll-Hess Hamiltonian order and property operator transformation.
Main Results:
- Established optimal Gauss-type basis sets for accurate electron density calculations.
- Demonstrated the significant impact of basis set choice and contraction scheme on results.
- Quantified the influence of electron correlation and numerical integration precision.
- Showcased the convergence behavior with respect to the Douglas-Kroll-Hess Hamiltonian order.
Conclusions:
- Basis set convergence is critical for reliable relativistic electron density calculations.
- The developed Gauss-type basis sets provide a robust foundation for future studies.
- Accurate treatment of relativistic effects and electron correlation is essential for high-precision computational chemistry.
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