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URN: urn:nbn:de:swb:90-758584
Originalveröffentlichung
DOI: 10.5194/acp-17-10733-2017

Direct molecular-level characterization of different heterogeneous freezing modes on mica – Part 1

Abdelmonem, Ahmed

Abstract:
The mechanisms behind heterogeneous ice nucleation are of fundamental importance to the prediction of the occurrence and properties of many cloud types, which influence climate and precipitation. Aerosol particles act as cloud condensation and freezing nuclei. The surface–water interaction of an ice nucleation particle plays a major, not well explored, role in its ice nucleation ability. This paper presents a real-time molecular-level comparison of different freezing modes on the surface of an atmospherically relevant mineral surface (mica) under varying supersaturation conditions using second-harmonic generation spectroscopy. Two sub-deposition nucleation modes were identified (one- and two-stage freezing). The nonlinear signal at the water–mica interface was found to drop following the formation of a thin film on the surface regardless of (1) the formed phase (liquid or ice) and (2) the freezing path (one or two step), indicating similar molecular structuring. The results also revealed a transient phase of ice at water–mica interfaces during freezing, which has a lifetime of around 1 min. Such information will have a significant i ... mehr


Zugehörige Institution(en) am KIT Institut für Meteorologie und Klimaforschung - Atmosphärische Aerosolforschung (IMK-AAF)
Publikationstyp Zeitschriftenaufsatz
Jahr 2017
Sprache Englisch
Identifikator ISSN: 1680-7324, 1680-7316
URN: urn:nbn:de:swb:90-758584
KITopen ID: 1000075858
Erschienen in Atmospheric chemistry and physics
Band 17
Heft 17
Seiten 10733–10741
Bemerkung zur Veröffentlichung Gefördert durch den KIT-Publikationsfonds
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