A series of hyperthermal energy, ion/surface scattering experiments were performed. These studies examined and characterized some of the many processes occurring in energetic gas/surface collisions. In the scattering of Ne+ on Si(001), the precise amount of momentum, transferred to the surface upon collision, was measured under various conditions. Models that incorporate image charge interactions and inelastic energy loss were successfully applied to simulate the data. The first measurement of atom abstraction at an oxide surface was recorded in the scattering of NO+ on O/Al(111). Measurement of the product yield and energy distribution as a function of incident energy revealed the detailed reaction mechanism. The growth and erosion of SiO2 thin films under O+ bombardment was studied. Isotopic labeling experiments combined with mass-, energy-, and angular-resolved detection provided compelling evidence for a direct Eley-Rideal abstraction of adsorbed oxygen by incident O+ ions. This reaction pathway competes directly with sputtering channels in the formation of scattered O2- and SiO+. The conclusions from this work help in the modeling of spacecraft interactions with the LEO environment, e.g., vehicle drag, spacecraft charging, oxidation/degradation of exposed surfaces, and the formation of signatures.

As computing power increases, a growing number of macroscopic phenomena are modeled at the molecular level. Consequently, new requirements are generated for the understanding of molecular dynamics in exotic conditions. This book illustrates the importance of detailed chemical dynamics and the role it plays in the phenomenology of a number of extreme environments. Each chapter addresses one or more extreme environments, outlines the associated chemical mechanisms of relevance, and then covers the leading edge science that elucidates the chemical coupling. The chapters exhibit a balance between theory and experiment, gas phase, solid state, and surface dynamics, and geophysical and technical environments. Sample Chapter(s). Chapter 1.1: Introduction (203 KB). Chapter 1.2: Chemistry at High Temperatures and Pressures (99 KB). Chapter 1.3: High Temperature Chemistry in the Atmosphere (82 KB). Chapter 1.4: Low Temperature Chemistry (90 KB). Chapter 1.5: Conclusions (131 KB). Contents: Exploring Chemistry in Extreme Environments: A Driving Force for Innovation (M R Berman); Chemistry Under Extreme Conditions: Cluster Impact Activation (T Raz & R D Levine); Nonequilibrium Chemistry Modeling in Rarefied Hypersonic Flows (I D Boyd); Chemical Dynamics in Chemical Laser Media (M C Heaven); From Elementary Reactions to Complex Combustion Systems (C Schulz et al.); The Gas-Phase Chemical Dynamics Associated with Meteors (R A Dressler & E Murad); Dynamics of Hypervelocity Gas/Surface Collisions (D C Jacobs); Surface Chemistry in the Jovian Magnetosphere Radiation Environment (R E Johnson); Dynamics of Atomic Oxygen Induced Polymer Degradation in Low Earth Orbit (T K Minton & D J Garton); Atomic-Level Properties of Thermal Barrier Coatings: Characterization of MetalOCoCeramic Interface (A Christensen et al.); Molecular Dynamics Simulations of Detonations (C T White et al.). Readership: Scientists engaged in cross-disciplinary work and chemists studying multidisciplinary problems."

As computing power increases, a growing number of macroscopic phenomena are modeled at the molecular level. Consequently, new requirements are generated for the understanding of molecular dynamics in exotic conditions.This book illustrates the importance of detailed chemical dynamics and the role it plays in the phenomenology of a number of extreme environments. Each chapter addresses one or more extreme environments, outlines the associated chemical mechanisms of relevance, and then covers the leading edge science that elucidates the chemical coupling. The chapters exhibit a balance between theory and experiment, gas phase, solid state, and surface dynamics, and geophysical and technical environments.

Understanding mechanisms at the molecular level is essential for interpreting and predicting the outcome of processes in all fields of chemistry. Insight into gas-surface reaction dynamics can be gained through molecular beam scattering experiments combined with classical trajectory simulations. In particular, energy exchange and thermal accommodation in the initial collision, the first step in most chemical reactions, can be probed with these experimental and computational tools.

100 keV) of neutral hydrogen 7 atoms . The design of the cesium jettarget intended to achieve the 7 following goals : - Supersonic nozzle - cooled skimmer system to increase the fraction 8 of the total nozzle flux Jn which is used as the jettarget flux Jt, 8 = Jt/Jn, from low values 8