Homonuclear Diatomics Research Articles

Charge Exchange between Homonuclear Diatomic Molecules and Protons

The impact-parameter method was adapted to the calculation of proton—homonuclear-diatomic-molecule charge transfer. In doing so, matrix elements of the Brinkman—Kramers type are calculated and subsequently adjusted through the Mapleton ratio. The cross section is actually determined by finding a sort of hard-sphere radius. The relative importance of transfer from various molecular orbitals and to various hydrogen orbitals is considered. Transfers to hydrogen orbitals having principal quantum numbers of less than 5 must be considered. Transfers from the various molecular orbitals are considered. The calculations for O2 and N2 agree reasonably well with experiment, and the program may be readily applied to other homonuclear diatomics having a similar electronic structure.

Ionization of Molecules at Low Energies

A general formal theory is developed for the autoionization of molecules at energies within a few electron volts or less of threshold, specifically to include effects of the interaction of an excited Rydberg electron with the rotating, vibrating molecule—ion to which it is bound. The dominant coupling mechanism involves conversion of vibrational energy to electronic energy and is most efficient when the core can undergo a single quantum jump. A number of simplifications and approximations are discussed. Some of these are used in an application of the theory to the autoionization of H2. Autoionization rates are computed for a number of vibronic Rydberg states of this molecule, and are consistent with the available data. Model calculations for heteronuclear diatomics are presented to show how the presence of a vibrating dipole in the molecular core enhances the rates of autoionization, in comparison with the rates in homonuclear diatomics where vibrating quadrupoles stimulate the process. Several experiments are suggested, particularly the measurement of the angular distributions of electrons detached from heteronuclear diatomics.

Homonuclear Diatomic One-Electron Eigenfunctions as Basis Sets

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Theory of Rotational Excitation of Homonuclear Diatomic Molecules by Slow Electrons: Application toN2andH2

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Simple Orbitals for Molecular One-Layer Puffs

The radial wave equation of an electron in a spherically symmetrical field[Complex chemical formula](potential field of a molecular one-layer puff) is solved. For this purpose the outer part of the radial function (r≥ρ) is approximated by the asymptotic expansion of the Whittaker function Wk, l+½(y). To improve the accuracy a converging factor is used. A comparison is done with existing exact or approximate calculations on phantom-center puffs (q0=0). The results are satisfactory for energies and wavefunctions as well. The influence of the choice of origin on the orbital energy in homonuclear diatomics is discussed. In ``non-phantom-'' center puffs (q0≠0), assuming the bare-nuclei approach, many inner radial wavefunctions (r≤ρ) were found hydrogenic to a very good approximation.

Analytic Self-Consistent Field Wavefunctions and Computed Properties for Homonuclear Diatomic Molecules

The analytic and computational framework for Hartree—Fock—Roothaan calculations on homonuclear diatomic molecules is presented. Several approaches to calculating the wavefunction are sketched as well as methods of computing molecular properties from the wavefunction. Emphasis is given to the efficient organization of these calculations for existing digital computers. Typical results obtained through the application of the programs and techniques developed are presented for the fluorine molecule.

Chemical Binding in Homonuclear Diatomic Molecules1

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemical Binding in Homonuclear Diatomic Molecules1Rolland R. Rue and Klaus RuedenbergCite this: J. Phys. Chem. 1964, 68, 7, 1676–1706Publication Date (Print):July 1, 1964Publication History Published online1 May 2002Published inissue 1 July 1964https://doi.org/10.1021/j100789a004RIGHTS & PERMISSIONSArticle Views98Altmetric-Citations27LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (3 MB) Get e-Alerts

Numerical Calculations by the Hellmann—Feynman Procedure

Simple calculations of atomic forces and of force constants in homonuclear diatomics confirm the unreliability of the Hellmann—Feynman procedure for calculating molecular forces unless very accurate one-electron densities are used. Electronic forces are extremely sensitive to polarization and to small density changes near atomic centers, so that in general they cannot be used alone to determine accurately a totally a priori one-electron density. They may, however, be useful in testing the features of the density obtained from a variational wavefunction.

Thomas—Fermi Homonuclear Diatomic Molecule. I. Method of Solution and Atomic Interaction Potential

The Thomas—Fermi equation, without exchange, has been solved numerically for the neutral diatomic homonuclear molecule. The method of solution and results of the energy integrations are given. Scaling of the nuclear separation parameter and of the energy units permits calculation of a universal interaction potential applicable to all atomic numbers at all separations. Electronic energies are estimated to have a numerical precision of better than 1 part in 104.

Some Problems in the Theory of Homonuclear Diatomic Molecules

Some Problems in the Theory of Homonuclear Diatomic Molecules

The application of perturbation theory to the calculation of force constants

By the application of perturbation theory the following expression is derived for the force constant of a diatomic molecule: K 2Z aZ b = e 2 r 0 3 − ∑ n e 2〈ρ 0n(i)∣ cos θ ai r 2 ai 〉〈ρ 0n(i)∣ cos θ bi r 2 bi 〉 (E n−E 0) where r 0 is the equilibrium internuclear separation, and ρ 0 n is the transition density between the ground state and the nth excited state. By comparing the above expression with the experimental variation of K with r 0, it is shown that the sum over states is almost constant for isoelectronic molecules, and varies regularly for molecules belonging to the same group. Some of the intergrals which are required for evaluating this sum are given for the first row homonuclear diatomics. It is shown how this perturbation method may be extended to polyatomic molecules.

Asymmetry of Inner Electron Distributions in Homonuclear Diatomic Molecules

Disturbances in the distributions of inner shell electrons due to bond formation in homonuclear diatomic molecules have been investigated using a Fermi-Thomas type statistics. In the majority of molecules examined the disturbance seems to penetrate only to the shell directly beneath the valence shell. Plots of the number of electrons disturbed versus atomic number are periodic, the disturbance being less for the alkali molecules than for the halogens. In any one group, these plots are remarkably linear. This behavior has permitted us to calculate the bond distance in Rb2. It is found to be 4.28A. This value is to be compared with the distance 4.32A between nearest neighbors in the metal.

Infra-Red Absorption by Homonuclear Diatomic Molecules

Infra-Red Absorption by Homonuclear Diatomic Molecules

Note on the Nuclear Electric Quadrupole Spectrum of a Homonuclear Diatomic Molecule in a Magnetic Field

Note on the Nuclear Electric Quadrupole Spectrum of a Homonuclear Diatomic Molecule in a Magnetic Field