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Results for “hydrogen molecule”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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NASA NTRS1979

Rotational excitation of hydrogen molecules by collisions with hydrogen atoms

Rate constants for rotational excitation of hydrogen molecules by collisions with hydrogen atoms have been obtained from quantum-mechanical calculations for kinetic temperatures between 100 and 5000 K. These calculations involve the rigid-rotator approximation, but other possible sources of error should be small. The calculations indicate that the early values of Nishimura are larger than accurate rigid-rotator values by about a factor of 20 or more.

Green, S.↗
NASA NTRS1973

Calculated dipole moment and energy in collision of a hydrogen molecule and a hydrogen atom

Calculations were carried out using three Slater-type 1s orbitals in the orthogonalized valencebond theory of McWeeny. Each orbital exponent was optimized, the H2 internuclear distance was varied from 7.416 x 10 to the -11th power to 7.673 x 10 to the -11th power m (1.401 to 1.450 bohrs). The intermolecular distance was varied from 1 to 4 bohrs (0.5292 to 2.117 x 10 to the 10th power). Linear, scalene, and isosceles configurations were used. A weighted average of the interaction energies was taken for each intermolecular distance. Although energies are tabulated, the principal purpose was to calculate the electric dipole moment and its derivative with respect to H2 internuclear distance.

Patch, R. W.↗
NASA NTRS1974

Short-range interaction between hydrogen molecules

Recent calculations of the ground state energy of a system of four hydrogen atoms are reviewed with the aim of discerning the short-range repulsive part of the interaction potential between two hydrogen molecules. Extended-basis CI calculations which include a diffuse 2p orbital appear to be capable of determining the total interaction energy between to hydrogen molecules for any separation. Consistent results of such calculations suggest that the potential for intermolecular separations in the region from 1 to 2.5 A can now be specified to better than 10% with considerable confidence. Analytic fits to spherical averages of these results are presented.

Mcmahan, A. K.↗
NASA NTRS1980

Semiclassical study of the quenching of excited-state fluorine atom by hydrogen molecule - Comparison between reactive and nonreactive processes

Semiclassical calculations are carried out for the quenching of excited-state fluorine atom by collinear collisions with hydrogen molecule. The overall quenching probability is the sum of two contributions: the reactive quenching probability associated with the formation of hydrogen fluoride and the nonreactive quenching probability leading to ground-state fluorine atom and hydrogen molecule. The reactive probability is greater in the threshold region of the collision energy, whereas the nonreactive probability dominates for energies above the threshold region.

Yuan, J.-M.↗