Solving the electron and electron-nuclear Schroedinger equations for the excited states of helium atom with the free iterative-complement-interaction method
- Quantum Chemistry Research Institute, JST CREST, Kyodai Katsura Venture Plaza 106, Goryo Oohara 1-36, Nishikyo-ku, Kyoto 615-8245 (Japan) and Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510 (Japan)
Very accurate variational calculations with the free iterative-complement-interaction (ICI) method for solving the Schroedinger equation were performed for the 1sNs singlet and triplet excited states of helium atom up to N=24. This is the first extensive applications of the free ICI method to the calculations of excited states to very high levels. We performed the calculations with the fixed-nucleus Hamiltonian and moving-nucleus Hamiltonian. The latter case is the Schroedinger equation for the electron-nuclear Hamiltonian and includes the quantum effect of nuclear motion. This solution corresponds to the nonrelativistic limit and reproduced the experimental values up to five decimal figures. The small differences from the experimental values are not at all the theoretical errors but represent the physical effects that are not included in the present calculations, such as relativistic effect, quantum electrodynamic effect, and even the experimental errors. The present calculations constitute a small step toward the accurately predictive quantum chemistry.
- OSTI ID:
- 21104027
- Journal Information:
- Journal of Chemical Physics, Vol. 128, Issue 15; Other Information: DOI: 10.1063/1.2904871; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
Similar Records
Solving the Schroedinger equation for helium atom and its isoelectronic ions with the free iterative complement interaction (ICI) method
SOLVING THE NON-BORN-OPPENHEIMER SCHROeDINGER EQUATION FOR THE HYDROGEN MOLECULAR ION WITH THE FREE COMPLEMENT METHOD. II. HIGHLY ACCURATE ELECTRONIC, VIBRATIONAL, AND ROTATIONAL EXCITED STATES