ASTROCHEMISTRY – a MOLECULAR APPROACH CHEM657/ASTR657 Ralf I

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ASTROCHEMISTRY – A MOLECULAR APPROACH CHEM657/ASTR657 Ralf I. Kaiser [email protected] The ultimate goal of this class is to understand and to predict the fundamental chemical and physical processes leading to the formation of molecules ranging from diatomics (H2) to complex, astrobiologically important species (amino acids, sugars) in the interstellar medium and in our Solar System – both in the gas phase (e.g. molecular clouds, star forming regions, atmospheres of planets and their moons) and in the solid state (interstellar grains, icy planets and moons, comets). A detailed understanding of these processes is imperative to correctly interpret data from astronomical observations and from actual space missions and to develop realistic models how distinct interstellar and Solar System environments are processed chemically. OVERVIEW 1. elements and molecules in the interstellar medium (neutrals, cations, anions) 2. overview of interstellar environments 3. molecules in interstellar environments I: gas phase 4. molecules in interstellar environments II: ices GAS PHASE PROCESSES 5. characteristics & energetics of a chemical reaction 6. direct versus indirect reactions; barriers versus barrier-less 7. collision theory gas phase 8. reaction classes in interstellar chemistry: understanding why molecules are formed in the ISM 9. retro-synthesis gas phase chemistry: prediction where molecules are formed in the ISM SOLID STATE REACTIONS 10. thermal reactions on interstellar grains 11. suprathermal versus thermal rate constants 12. collision theory solid state (CASINO and TRIM) 13. retro-synthesis solid state chemistry 14. experimental studies of interaction of ionizing radiation with matter APPLICATIONS 15. formation of astrobiologically relevant molecules (sugars, amino acids) 16. charged particle processing of interstellar and Solar System ices (KBOs, icy satellites, comets) 17. gas phase chemistry in the ISM and in planetary atmospheres (Mars, Titan, Gas Planets) The first organizational meeting will be in Bilger Hall, Room 212, January 9 (Monday), 9:30 am (arrangement of class schedule, literature; if you cannot come to this meeting, please email me) .

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