Quantum Monte Carlo ground state energies for the singly charged ions from Li through Ar
P Maldonado1, A Sarsa, E Buendía
1Departamento de Física, Campus de Rabanales Edif. C2, Universidad de Córdoba, Córdoba E-14071, Spain.
The Journal of Chemical Physics
|August 17, 2010
Summary
Quantum Monte Carlo calculations determined ground state energies for ions Li(+) to Ar(+) and Li(-) to Cl(-). This study provides accurate ionization potentials and electron affinities for these charged species.
Area of Science:
- Computational Chemistry
- Quantum Mechanics
- Atomic Physics
Background:
- Accurate calculation of atomic and ionic properties is crucial for understanding chemical behavior.
- Quantum Monte Carlo (QMC) methods offer a powerful approach for solving the Schrödinger equation.
Purpose of the Study:
- To compute nonrelativistic frozen nucleus all-electron Quantum Monte Carlo ground state energies for positive and negative ions.
- To determine ionization potentials and electron affinities from the calculated ground state energies.
Main Methods:
- Employed explicitly correlated wave functions with a single configuration model function times a Jastrow factor.
- Utilized a restricted multiconfiguration expansion for ions with significant multiconfiguration character.
Main Results:
- Achieved high accuracy for ions across the second and third periods, comparable to neutral atoms.
- Ground state energies for charged species were calculated with high fidelity.
Conclusions:
- The QMC methodology provides accurate ground state energies for a range of atomic ions.
- Calculated ionization potentials and electron affinities are reliable benchmarks.
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