Theoretical Vibrational Energy Levels of H2 Associated with Various Combinations of Molecular-Orbital Configurations

Journal Article · Mon Jan 01 04:00:00 EST 1962 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.1733299· OSTI ID:4771950

Leies, Gerard M.

A theoretical examination was made of the influence of various MO configurations on the spacing of the vibrational levels of H₂. Eleven previously determined potential curves for the H₂ ground state, based upon LC STO MO wavefunctions with configuration interaction, were used to calculate vibrational-energy levels and their first differences DELTA G. Comparison of the 11 curves of DELTA G vs vibrational quantum nurnber v shows that only when the wavefunction contains the configuration ( sigma _u1s sigma _u1s') does the DELTA G curve have a shape similar to that of the experimental DELTA G curve. The combination of ( sigma _g1s sigma _gls') and ( sigma _u 1s sigma _u1s') provides left-right correlation or variable ionicity and this ionicity is found to vary in the same manner as the curvature of the DELTA G curve. The addition of ( sigma _g2s sigma _g2p), which gives in-out correlation, and ( pi _u2p pi _u2p), which provides angular correlation, to the wavefunction raises the DELTA G curve especially at large v. The use of DELTA G curves obtained from simple wavefunctions to estimate dissociation energies is discussed.

• Research Organization: Georgetown Univ., Washington, D.C.
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-002088
• OSTI ID: 4771950
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 7 Vol. 37; ISSN JCPSA6; ISSN 0021-9606
• Publisher: American Institute of Physics (AIP)
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR DISTRIBUTION
CONFIGURATION
DECOMPOSITION
ENERGY LEVELS
HYDROGEN
IONIZATION
MOLECULES
ORBITS
QUANTUM MECHANICS
VIBRATIONS