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Published on: May 27, 2020
Relativistic quantum Monte Carlo method using zeroth-order regular approximation Hamiltonian.
Yutaka Nakatsuka1, Takahito Nakajima, Maho Nakata
1Department of Applied Chemistry, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan. yutaka@qcl.t.u-tokyo.ac.jp
The Journal of Chemical Physics
|February 9, 2010
Summary
We introduce a new relativistic quantum Monte Carlo method using the zeroth-order regular approximation (ZORA) Hamiltonian. This ZORA-QMC approach accurately captures relativistic and electron correlation effects for atoms Li-Ne.
Area of Science:
- Quantum chemistry
- Computational physics
- Relativistic quantum mechanics
Background:
- Quantum Monte Carlo (QMC) methods are powerful tools for studying electron correlation.
- Incorporating relativistic effects into QMC calculations remains a significant challenge.
- The zeroth-order regular approximation (ZORA) offers a computationally tractable relativistic Hamiltonian.
Purpose of the Study:
- To develop a novel relativistic treatment within the QMC framework.
- To derive and implement a ZORA local energy for QMC calculations.
- To simultaneously evaluate relativistic and electron correlation effects.
Main Methods:
- Development of a new ZORA local energy expression.
- Application of variational Monte Carlo (VMC) calculations.
- Optimization of Jastrow-Slater wave functions.
- Calculation of ionization potentials for first-row atoms (Li-Ne).
Main Results:
- The novel ZORA local energy was successfully derived and implemented.
- The ZORA-QMC method demonstrated its capability to recover relativistic effects.
- The method achieved comparable electron correlation recovery to nonrelativistic QMC.
- Accurate ionization potentials were obtained for Li-Ne atoms.
Conclusions:
- The proposed ZORA-QMC method provides an effective way to include relativistic effects in QMC.
- This approach allows for simultaneous treatment of relativistic and correlation energies.
- The method shows promise for accurate calculations of atomic and molecular properties.
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