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Updated: Aug 23, 2025
12:11
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
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A comparison between the one- and two-step spin-orbit coupling approaches based on the ab initio density matrix
Huanchen Zhai1, Garnet Kin-Lic Chan1
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
The Journal of Chemical Physics
|November 1, 2022
Summary
Accurate treatment of spin-orbit coupling (SOC) and electron correlation is key for f-element chemistry. A new one-step ab initio density matrix renormalization group method offers benefits for calculating low-energy spectra in specific systems.
Area of Science:
- Computational chemistry
- Quantum chemistry
- Materials science
Background:
- Understanding f-element chemistry requires accurate treatment of electron correlation and spin-orbit coupling (SOC).
- Two common approaches are the one-step and two-step state interaction methods.
Purpose of the Study:
- To implement and evaluate an ab initio density matrix renormalization group (DMRG) method with a one-step treatment of SOC.
- To compare the one-step approach with traditional two-step methods for calculating low-energy spectra.
Main Methods:
- Implementation of ab initio DMRG incorporating a one-step SOC treatment.
- Application to benchmark systems: a dysprosium octahedral complex and a bridged dimer.
Main Results:
- The developed one-step DMRG-SOC method provides a viable alternative to two-step approaches.
- Identification of specific problem characteristics where the one-step method yields superior results for low-energy spectra.
Conclusions:
- The one-step DMRG-SOC approach is beneficial for specific f-element systems.
- This method enhances the accuracy and efficiency of computational studies in f-element chemistry.
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