Description: Das Projekt "Oberflaechenphotochemie" wird vom Umweltbundesamt gefördert und von Universität Oldenburg, Fachbereich 9 Chemie, Arbeitsgruppe Physikalische Chemie I durchgeführt. There are striking differences between the photochemistry of free and adsorbed molecules. The basic underlying reasons are connected with the creation of new electronic states, new excitation and de-excitation channels and the dramatically different life times of excited states for adsorbate-substrate systems. This fact is at the root of key processes in atmospheric reactions on particulates, astrochemistry, etching, lithography, carbon gasification, photolytic water decomposition. For example: the absorption cross section for decompositon of water in the near ultraviolet is several orders of magnitude higher when the water is adsorbed on a Pd-metal surface than for free water or ice. This fact can have consequences for heterogeneous photochemical reactions in the atmosphere, which to date have not been studied at all. The project claims to deepen our knowledge of surface photochemistry of small molecules in general and use this knowledge to study atmospherically relevant heterogeneous surface photochemistry of water (co-)-adsorbed on carbonaceous materials (carbon, soot ...), metal oxides and other atmospherically relevant substrates. Interesting co-adsorbates are NOx, ozone, halogen and sulphur containing molecules. The project has only recentely started. Hauptverantwortliche Institution: Stichting Fundamenteel Inderzoek der Materie, Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam, Niederlande, Tel.: +31-20 6081234, Fax: +31-20 6684106.
Types:
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Oldenburg ? Ozon ? Gerinne ? Substrat ? Wasserstraße ? Amsterdam ? Halogen ? Kernphysik ? Kohlenstoff ? Metalloxid ? Oxid ? Photochemie ? Physikalische Chemie ? Schwefel ? Niederlande ? Pflanzenwurzel ? Photolyse ? Stickoxide ? Absorption ? Vergasung ? Adsorption ? Ruß ? Regenwasser ? Photochemische Reaktion ? Studie ? Wasseroberfläche ? Wasserstand ? Atmosphäre ? Atmosphärenchemie ? Chemische Reaktion ? Produktlebensdauer ? Angeregter-Zustand ? Molekuel ? Oberflaechenchemie ? Absorptionsquerschnitt ?
Region: Lower Saxony
Bounding box: 9.16667° .. 9.16667° x 52.83333° .. 52.83333°
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 1998-09-01 - 2002-08-31
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