Excitation of H2 at large internuclear separation:  outer well states and continuum resonances

This is an analytical investigation of well-known 10–12 potential of hydrogen–hydrogen covalent bond. In this research, we will make an elaboration of the well-known 6–12 Lennard–Jones potential in case of this type of bond. Though the results are illustrated in many text books and literature, an analytical analysis for these potentials is missing almost everywhere. The power laws are valid for small radial distances, which are calculated to some extent. The internuclear separation as well as the binding energy of the hydrogen molecule are evaluated with success.

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Multiple Solutions to the Hartree–Fock Problem. II. Molecular Wavefunctions in the Limit of Infinite Internuclear Separation

The Journal of Chemical Physics ◽

10.1063/1.1671628 ◽

1969 ◽

Vol 50 (9) ◽

pp. 3789-3797 ◽

Cited By ~ 26

Author(s):

Harry F. King ◽

Richard E. Stanton

Keyword(s):

Multiple Solutions ◽

Internuclear Separation ◽

Hartree Fock ◽

Molecular Wavefunctions

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A re-examination of the adiabatic correction term for the hydrogen molecule

Canadian Journal of Chemistry ◽

10.1139/v76-093 ◽

1976 ◽

Vol 54 (4) ◽

pp. 651-656 ◽

Cited By ~ 7

Author(s):

Huw O. Pritchard ◽

Lutosław Wolniewicz

Keyword(s):

Energy Level ◽

Hydrogen Molecule ◽

Vibrational Energy ◽

Correction Term ◽

Internuclear Separation ◽

Vibrational Energy Level ◽

The Difference ◽

The One

The adiabatic coupling correction term [Formula: see text] has been evaluated by two methods, the one used by Kołos and Wolniewicz in 1964 and the one suggested by Kari, Chan, Hunter, and Pritchard in 1973. The difference between the two procedures for H2 amounts to 0.04 cm−1 and is almost independent of internuclear separation in the range R = 1.0–1.8 a.u. Thus, the method of computing the ΔR-term does not affect the vibrational energy level spacings.

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Adiabatic Potentials and Oscillator Strengths of Thallium-Noble Gas Atom Pairs

Zeitschrift für Naturforschung A ◽

10.1515/zna-1982-0404 ◽

1982 ◽

Vol 37 (4) ◽

pp. 325-333

Author(s):

E. Czuchaj

Keyword(s):

Noble Gas ◽

Semiempirical Method ◽

Oscillator Strengths ◽

Continuum Emission ◽

Interatomic Potentials ◽

Internuclear Separation ◽

Molecular Oscillator ◽

Asymptotic Values ◽

Atom Pairs

Abstract Baylis' semiempirical method has been applied for calculating interatomic potentials and oscillator strengths as a function of internuclear separation of the thallium-noble gas systems. The new potentials for the four lowest molecular states of each diatomic have been compared with the corresponding ones deduced by Cheron et al. from the measurement of continuum emission intensities on the extreme wings of the Tl resonance lines due to noble gas perturbers. The calculated potentials differ considerably from the latter ones. The molecular oscillator strengths have been calculated for both the allowed and the forbidden Tl transitions. The asymptotic values of the first ones are compared with the corresponding atomic oscillator strengths of other calculations and measurements. The agreement is generally quite good.

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THE USE OF THE HELLMANN–FEYNMAN THEOREM TO CALCULATE MOLECULAR ENERGIES

Canadian Journal of Chemistry ◽

10.1139/v60-287 ◽

1960 ◽

Vol 38 (11) ◽

pp. 2117-2127 ◽

Cited By ~ 15

Author(s):

Richard F. W. Bader

Keyword(s):

Variational Method ◽

Variational Methods ◽

Present Method ◽

Molecular Orbitals ◽

Internuclear Separation ◽

Electron Densities ◽

Empirical Expression ◽

Atomic Orbitals ◽

Helium Atoms ◽

Feynman Theorem

The Hellmann–Feynman theorem has been employed to calculate the repulsion between two helium atoms and the molecular energies of H2 and H3. The method of molecular orbitals was used to determine the necessary expressions for the electron densities. The screening constants of the atomic orbitals comprising the molecular orbitals were treated as functions of the internuclear separation according to an empirical expression which duplicates very closely the "best" values for these parameters as determined by the variational method. The results of the calculations indicate that the present method is capable of yielding estimates of molecular energies which are comparable to those obtained by the more elaborate and time-consuming variational methods.

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