| 357 K 11 pp. |   | |
| View Document |   | |
|   | ||
| Title | Research Directed at Developing a Classical Theory to Describe Isotope Separation of Polyatomic Molecules Illuminated by Intense Infrared Radiation. Final Report for period May 7, 1979 to September 30, 1979; Extension December 31, 1997 | |
| Author(s) | Lamb, W. E. Jr. | |
| Publication Date | December 1981 | |
| Report Number | DOE/ET/33011-T1 | |
| Unique Identifier | ACC0089 | |
| Other Numbers | Legacy ID: DE82009652; OSTI ID: 5340529 | |
| Research Org | University of Arizona, Tucson (USA). Optical Sciences Center | |
| Contract No | AS02-77ET33011 | |
| Sponsoring Org | US Department of Energy | |
| Subject | 400203 -- Isotope Exchange & Isotope Separation-- (-1987) ;400500 -- Photochemistry; ;Laser Isotope Separation -- Research Programs; Sulfur Fluorides -- Dissociation; Electric Fields; Excitation; Interatomic Forces; Laser Radiation; Photolysis | |
| Keywords | Chemical Reactions; Decomposition; Electromagnetic Radiation; Energy-level Transitions; Fluorides; Fluorine Compounds; Halides; Halogen Compounds; Isotope Separation; Photochemical Reactions; Radiations; Separation Processes; Sulfur Compounds | |
| Related Web Pages | Willis E. Lamb, Jr., the Hydrogen Atom, and the Lamb Shift | |
| Abstract | This final report describes research on the theory of isotope separation produced by the illumination of polyatomic molecules by intense infrared laser radiation. This process is investigated by treating the molecule, sulfur hexafluoride, as a system of seven classical particles that obey the Newtonian equations of motion. A minicomputer is used to integrate these differential equations. The particles are acted on by interatomic forces, and by the time-dependent electric field of the laser. We have a very satisfactory expression for the interaction of the laser and the molecule which is compatible with infrared absorption and spectroscopic data. The interatomic potential is capable of improvement, and progress on this problem is still being made. We have made several computer runs of the dynamical behavior of the molecule using a reasonably good model for the interatomic force law. For the laser parameters chosen, we find that typically the molecule passes quickly through the resonance region into the quasi-continuum and even well into the real continuum before dissociation actually occurs. When viewed on a display terminal, the motions are exceedingly complex. As an aid to the visualization of the process, we have made a number of 16 mm movies depicting a three-dimensional representation of the motion of the seven particles. These show even more clearly the enormous complexity of the motions, and make clear the desirability of finding ways of characterizing the motion in simple ways without giving all of the numerical detail. One of the ways to do this is to introduce statistical parameters such as a temperature associated with the distribution of kinetic energies of the single particle. We have made such an analysis of our data runs, and have found favorable indications that such methods will prove useful in keeping track of the dynamical histories. | |
| 357 K 11 pp. |   | |
| View Document |   | |
|   | ||