K. L. Wendell

Dynamics of the reaction of F+ with D2

The energy and angular distribution of the ionic products from the reaction F+(D2,D)FD+ were measured as a function of primary ion energy ranging from 0.7 to 12.5 eV in the laboratory system. At the low energies the distribution showed a high degree of symmetry although some forward peaking was detectable. At the higher energies the distribution was asymmetric relative to ±90° indicating that the reaction was proceeding by an impulsive direct mechanism. A study of the exoergicity as a function of projectile energy shows that the bulk of the exothermicity of the reaction is converted into vibrational energy in the product ion. Failure to observe the reaction F+(D2,FD)D+ was attributed to a violation of the spin and symmetry conservation rules.

Internal energy of CH+ produced by the C+(H2,H)CH+ reaction

The energy spectrum of CH+ from the reaction C+(H2,H)CH+ was measured with a tandem mass spectrometer with improved energy resolution as a function of projectile kinetic energy. These spectra indicate the presence of the three lowest electronic states of CH+ and product vibrational excitation was observed in favorable cases. The internal energy distribution in the CH+ product was in satisfactory agreement with published results of phase space theory calculations for this reaction.

Reaction of C+(4P) with molecular hydrogen

The reaction of molecular hydrogen with C+ in its first excited state was studied over the energy range 0.5–9.0 eV in the laboratory system. The angular and energy distribution and the energy spectra indicated a direct mechanism for the reaction. The experimental measurements coupled with spin and symmetry considerations indicated that the CH+ product was in the a 3Π electronic state.

Rotational effects in the F+(H2,H)FH+ reaction

Accurate values of the exoergicity for F+(H2,H)FH+ and the deuterium analog have been determined at relative energies above 2 eV. These values imply FH+(FD+) internal energies greater than the rotationless dissociation energy which can be explained by a rotational energy barrier with partial tunneling through that barrier. Inferences are made as to the rotational and vibrational quantum numbers of the FH+(FD+) products which lead to a probable vibrational inversion. The effect of instrumental resolution is found to be important.

The reaction H2O+(D2,D)H2DO+

The reaction H2O+(D2,D)H2DO+ was studied over an energy range 0.75 to 69 eV using a scattering spectrometer. The results are consistent with previous measurements at higher temperature and it is concluded that the reaction proceeds via a direct mechanism down to energies below 0.14 eV. (AIP)