TY - THES A1 - Hugo, Edouard T1 - The H_1n+3 + H2 isotopic system T1 - origin of deuterium astrochemistry Y1 - 2008 DO - 10.23689/fidgeo-263 PB - Univ. Köln N2 - Dense cold molecular clouds reckoned to be stellar nurseries are the scene of an extreme molecular deuteration. Despite the cosmic D/H ratio of 10^{-5}, molecular species in prestellar cores are observed to contain nearly as much deuterium as hydrogen. This astonishing deuterium enrichment promoted by low temperatures is the work of H3+. It is the key species which unlocks the deuterium from its HD reservoir via reactions like H3+ + HD -> H2D+ + H_2 and drags it further to other species in successive reactions. For this reason, the H3+ + H2 isotopic system is outstandingly critical for the astrochemistry of cold environments. However, its understanding is yet incomplete and insufficient. This thesis thus focuses on the H3+ + H2 isotopic system from a theoretical, experimental and astronomical point of view giving a particular look into the role of nuclear spins... UR - http://hdl.handle.net/11858/00-1735-0000-0001-3191-9 ER -