Rotational-vibrational excitation in collisions of atomic ions with diatomic molecules. [1-3 KeV]

Thesis/Dissertation · Mon Jan 01 04:00:00 EST 1979

OSTI ID:5330437

Clark, J D

Rotational-vibrational excitation in atomic ion-diatomic molecule collisions is considered at intermediate ion projectile energies in the range of 1 to 3 keV. Collisions between He/sup +/ and H/sub 2/ are taken as an example. Three separate approaches are used in the description of the collision system. Inelastic energy transfer in collision systems and projectile scattering angle are calculated from a totally classical approach. Cross sections for scattering as a function of momentum transfer vector are calculated from a completely quantum mechanical approach. Molecular transitions from the ground rotational-vibrational state to several excited rotational-vibrational molecular states are considered. Here the nuclei are treated in the Born Approximation and the electrons are treated adiabatically. The potential function used in both of these calculations is composed of a short range repulsive and a long range attractive polarization term used to fit an H/sub 3//sup +/ potential surface from the literature. The third calculation treats molecular rotational-vibrational excitational quantum mechanically while the ion projectile is considered to have a well defined classical trajectory. Electron motion is again considered adiabatically. Molecular excitation probabilities from the ground rotational-vibrational state to several excited rotational-vibrational states are calculated. The potential form used in this last calculation explicitly takes into account the molecular electron distribution as well as terms corresponding to those in the above potential for the classical calculation and for the quantum mechanical calculation.

• Research Organization: Connecticut Univ., Storrs (USA)
• OSTI ID: 5330437
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ADIABATIC APPROXIMATION
BORN APPROXIMATION
CHARGED PARTICLES
CLASSICAL MECHANICS
COLLISIONS
ELEMENTS
ENERGY RANGE
ENERGY TRANSFER
ENERGY-LEVEL TRANSITIONS
EXCITATION
HELIUM IONS
HYDROGEN
ION COLLISIONS
ION-MOLECULE COLLISIONS
IONS
KEV RANGE
KEV RANGE 01-10
MECHANICS
MOLECULE COLLISIONS
MOMENTUM TRANSFER
NONMETALS
POLARIZATION
QUANTUM MECHANICS
SCATTERING