Termolecular Association.

Research has been initiated and conducted a on Termolecular Association in Gases and b on electron-excited atom collisions. A microscopic theory of ion-atom association in a gas was formulated. Connection with previous macroscopic treatments was established, and various dilemmas with previous macroscopic formula were noted and resolved. The present theory yields a much more accurate representation of the variation of the termolecular rate with gas density. A ten-channel eikonal treatment of electron-helium collisions was performed for a basis set of 1S, 2, 2P, 3S, 3P, 3D target states to yield the first theoretical results for the very basis orientation and alignment parameters for the 3D level of helium. Good agreement with recent measurements of the coincidence rate between the electron scattered inelastically in a given direction and the photon emitted in the cascade transition was obtained. Termolecular Association Atomic collision Electron Atom.