9419427 Manson The PI will develop and extend the theory of scattering of small mass particles by surfaces, with emphasis on interactions in which many quanta of energy are exchanged during the collision. The results of this work will provide useful information on the dynamics of surface atom motions and it will give information on the interaction potential between the atomic projectile and the surface thorough determination of the scattering form factors. The theory will be developed to handle the entire range of experimental conditions from fully quantum mechanical conditions to classical scattering. The PI will carry out extensive numerical calculations for helium atom scattering from clean and ordered surfaces, from adsorbates, and from Langmuir- Blodgett and self assembly films. This program of work will involve collaboration with some of the major experimental groups in helium-surface scattering, including those at Florida State, Gottingen, and Julich. *** This work involves developing the theory needed to interpret experimental work on the scattering of small mass particles, such as helium atoms, from surfaces. Such experiments give properties of the surface itself and also the interaction between the projectile and the surface. The computer will be used to simulate scattering from clean surfaces, surfaces with less than a layer of other types of atoms on it, and films of large molecules which can be put on layer by layer. These films are important in the production of computer chips. The PI plans to continue his long-term, close collaboration with experimental groups at Florida State University and at Gottinger and Julich in Germany. He is the principle theorist in the United States who helps interpret these experiments. ***
