Zeuch, Thomas

[["dc.bibliographiccitation.firstpage","15637"],["dc.bibliographiccitation.issue","45"],["dc.bibliographiccitation.journal","Physical Chemistry Chemical Physics"],["dc.bibliographiccitation.lastpage","15640"],["dc.bibliographiccitation.volume","14"],["dc.contributor.author","Carlsson, Philip Thomas Michael"],["dc.contributor.author","Keunecke, Claudia"],["dc.contributor.author","Krueger, Bastian Christopher"],["dc.contributor.author","Maass, Mona C."],["dc.contributor.author","Zeuch, Thomas"],["dc.date.accessioned","2018-11-07T09:14:50Z"],["dc.date.available","2018-11-07T09:14:50Z"],["dc.date.issued","2012"],["dc.description.abstract","Recent studies have suggested that the reaction of stabilised Criegee Intermediates (CIs) with sulfur dioxide (SO2), leading to the formation of a carbonyl compound and sulfur trioxide, is a relevant atmospheric source of sulfuric acid. Here, the significance of this pathway has been examined by studying the formation of gas phase products and aerosol during the ozonolysis of beta-pinene and 2-butene in the presence of SO2 in the pressure range of 10 to 1000 mbar. For b-pinene at atmospheric pressure, the addition of SO2 suppresses the formation of the secondary ozonide and leads to highly increased nopinone yields. A complete consumption of SO2 is observed at initial SO2 concentrations below the yield of stabilised CIs. In experiments using 2-butene a significant consumption of SO2 and additional formation of acetaldehyde are observed at 1 bar. A consistent kinetic simulation of the experimental findings is possible when a fast CI + SO2 reaction rate in the range of recent direct measurements [Welz et al., Science, 2012, 335, 204] is used. For 2-butene the addition of SO2 drastically increases the observed aerosol yields at higher pressures. Below 60 mbar the SO2 oxidation induced particle formation becomes inefficient pointing to the critical role of collisional stabilisation for sulfuric acid controlled nucleation at low pressures."],["dc.description.sponsorship","DFG [GRK 782]"],["dc.identifier.doi","10.1039/c2cp42992f"],["dc.identifier.isi","000310460400002"],["dc.identifier.pmid","23090096"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10222"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/27518"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Royal Soc Chemistry"],["dc.relation.issn","1463-9084"],["dc.relation.issn","1463-9076"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Sulfur dioxide oxidation induced mechanistic branching and particle formation during the ozonolysis of beta-pinene and 2-butene"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","6859"],["dc.bibliographiccitation.issue","15"],["dc.bibliographiccitation.journal","Physical Chemistry Chemical Physics"],["dc.bibliographiccitation.lastpage","6871"],["dc.bibliographiccitation.volume","16"],["dc.contributor.author","Buck, Udo"],["dc.contributor.author","Pradzynski, Christoph C."],["dc.contributor.author","Zeuch, Thomas"],["dc.contributor.author","Dieterich, Johannes M."],["dc.contributor.author","Hartke, Bernd"],["dc.date.accessioned","2018-11-07T09:46:25Z"],["dc.date.available","2018-11-07T09:46:25Z"],["dc.date.issued","2014"],["dc.description.abstract","Size selected water clusters are generated by photoionizing sodium doped clusters close to the ionization threshold. This procedure is free of fragmentation. Upon infrared excitation, size- and isomer-specific OH-stretch spectra are obtained over a large range of cluster sizes. In one application of this method the infrared spectra of single water cluster sizes are investigated. A comparison with calculations, based on structures optimized by genetic algorithms, has been made to tentatively derive cluster structures which reproduce the experimental spectra. We identified a single all-surface structure for n = 25 and mixtures with one or two interior molecules for n = 24 and 32. In another application the sizes are determined at which the crystallization sets in. Surprisingly, this process strongly depends on the cluster temperature. The crystallization starts at sizes below n = 200 at higher temperatures and the onset is shifted to sizes above n = 400 at lower temperatures."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft [ZE 890 1-1, 2, GRK 782]"],["dc.identifier.doi","10.1039/c3cp55185g"],["dc.identifier.fs","609790"],["dc.identifier.isi","000333121300004"],["dc.identifier.pmid","24603719"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10128"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/34864"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Royal Soc Chemistry"],["dc.relation.issn","1463-9084"],["dc.relation.issn","1463-9076"],["dc.rights.access","openAccess"],["dc.title","A size resolved investigation of large water clusters"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","26691"],["dc.bibliographiccitation.issue","48"],["dc.bibliographiccitation.journal","Physical Chemistry Chemical Physics"],["dc.bibliographiccitation.lastpage","26696"],["dc.bibliographiccitation.volume","16"],["dc.contributor.author","Pradzynski, Christoph C."],["dc.contributor.author","Dierking, Christoph W."],["dc.contributor.author","Zurheide, Florian"],["dc.contributor.author","Forck, Richard M."],["dc.contributor.author","Buck, Udo"],["dc.contributor.author","Zeuch, Thomas"],["dc.contributor.author","Xantheas, Sotiris S."],["dc.date.accessioned","2018-11-07T09:45:40Z"],["dc.date.available","2018-11-07T09:45:40Z"],["dc.date.issued","2014"],["dc.description.abstract","Water clusters with internally solvated water molecules are widespread models that mimic the local environment of the condensed phase. The appearance of stable (H2O)(n) cluster isomers having a fully coordinated interior molecule has been theoretically predicted to occur around the n = 20 size range. However, our current knowledge about the size regime in which those structures become energetically more stable has remained hypothetical from simulations in lieu of the absence of precisely size-resolved experimental measurements. Here we report size and isomer selective infrared (IR) spectra of (H2O) 20 clusters tagged with a sodium atom by employing IR excitation-modulated photoionization spectroscopy. The observed absorption patterns in the OH stretching region are consistent with the theoretically predicted spectra of two structurally distinct isomers of exceptional stability: a drop-like cluster with a fully coordinated (interior) water molecule and an edge-sharing pentagonal prism cluster in which all atoms are on the surface. The drop-like structure is the first experimentally detected water cluster exhibiting the local connectivity found in liquid water."],["dc.identifier.doi","10.1039/c4cp03642e"],["dc.identifier.fs","609795"],["dc.identifier.isi","000345453200034"],["dc.identifier.pmid","25231162"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/11429"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/34674"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Royal Soc Chemistry"],["dc.relation.issn","1463-9084"],["dc.relation.issn","1463-9076"],["dc.rights.access","openAccess"],["dc.title","Infrared detection of (H2O)(20) isomers of exceptional stability: a drop-like and a face-sharing pentagonal prism cluster"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","11695"],["dc.bibliographiccitation.issue","33"],["dc.bibliographiccitation.journal","Physical Chemistry Chemical Physics"],["dc.bibliographiccitation.lastpage","11705"],["dc.bibliographiccitation.volume","14"],["dc.contributor.author","Carlsson, Philip Thomas Michael"],["dc.contributor.author","Dege, Janina Elisabeth"],["dc.contributor.author","Keunecke, Claudia"],["dc.contributor.author","Krueger, Bastian Christopher"],["dc.contributor.author","Wolf, Jan Lennard"],["dc.contributor.author","Zeuch, Thomas"],["dc.date.accessioned","2018-11-07T09:15:06Z"],["dc.date.available","2018-11-07T09:15:06Z"],["dc.date.issued","2012"],["dc.description.abstract","The ozonolysis of cyclohexene is studied with respect to the pressure dependent formation of stable gas-phase products and secondary organic aerosol (SOA) as well as the influence of the presence of SO2. In addition the rate coefficient for the initial reaction cyclohexene + O-3 was determined at 295 K. The observed increase in CO and ethene yields at low pressures and the absence of ketene in the product spectrum confirm previously proposed reaction pathways forming these decomposition products. An enhanced ethene formation at pressures below 300 mbar coincides with drastically decreased aerosol yields pointing to a high influence on SOA formation of chemical activation driven dynamics in the vinylhydroperoxide channel. The static reactor experiments at 450 mbar in the presence of SO2 in the present study showed a similar sensitivity of additional particle formation to H2SO4 number densities as found in near-atmospheric flow reactor experiments [Sipila et al., Science, 2010, 327, 1243], a surprising result with regard to the very different experimental approaches. At low pressures (around 40 mbar) no significant new particle formation is observed even at high H2SO4 concentrations. These findings indicate that the collisional stabilisation of initial clusters is an important aspect for SOA formation processes involving sulfuric acid and organic compounds. The results may have implications for geo-engineering strategies based on stratospheric sulfur injection, but caution is mandatory when room temperature laboratory results are extrapolated to stratospheric conditions."],["dc.description.sponsorship","DFG [GRK 782]; Fonds der Chemischen Industrie"],["dc.identifier.doi","10.1039/c2cp40714k"],["dc.identifier.isi","000307017800015"],["dc.identifier.pmid","22825796"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10230"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/27593"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Royal Soc Chemistry"],["dc.relation.issn","1463-9076"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Pressure dependent aerosol formation from the cyclohexene gas-phase ozonolysis in the presence and absence of sulfur dioxide: a new perspective on the stabilisation of the initial clusters"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","10952"],["dc.bibliographiccitation.issue","23"],["dc.bibliographiccitation.journal","Physical Chemistry Chemical Physics"],["dc.bibliographiccitation.lastpage","10964"],["dc.bibliographiccitation.volume","13"],["dc.contributor.author","Wolf, Jan Lennard"],["dc.contributor.author","Richters, Stefanie"],["dc.contributor.author","Pecher, Josua"],["dc.contributor.author","Zeuch, Thomas"],["dc.date.accessioned","2018-11-07T09:01:53Z"],["dc.date.available","2018-11-07T09:01:53Z"],["dc.date.issued","2011"],["dc.description.abstract","The gas-phase ozonolysis of cyclic-alkenes (1-methyl-cyclohexene, methylene-cyclohexane, alpha-pinene, beta-pinene) is studied with respect to the pressure dependent formation of secondary organic aerosol (SOA). We find that SOA formation is substantially suppressed at lower pressures for all alkenes under study. The suppression coincides with the formation of ketene (alpha-pinene, 1-methyl-cyclohexene), ethene (1-methyl-cyclohexene) and the increased formation of CO (all alkenes) at lower reaction pressures. The formation of these products is independent of the presence of an OH scavenger and explained by an increased chemical activation of intermediate species in the hydroperoxide channel after the OH elimination. These findings underline the central role of the hydroperoxide pathway for SOA formation and give insight into the gas-phase ozonolysis mechanism after the stage of the Criegee intermediate chemistry."],["dc.identifier.doi","10.1039/c0cp02499f"],["dc.identifier.isi","000291113200012"],["dc.identifier.pmid","21442094"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10266"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/24542"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Royal Soc Chemistry"],["dc.relation.issn","1463-9076"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Pressure dependent mechanistic branching in the formation pathways of secondary organic aerosol from cyclic-alkene gas-phase ozonolysis"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","13608"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","Molecules"],["dc.bibliographiccitation.lastpage","13622"],["dc.bibliographiccitation.volume","18"],["dc.contributor.author","Seidel, Lars"],["dc.contributor.author","Hoyermann, Karlheinz"],["dc.contributor.author","Mauss, Fabian"],["dc.contributor.author","Nothdurft, Joerg"],["dc.contributor.author","Zeuch, Thomas"],["dc.date.accessioned","2018-11-07T09:17:45Z"],["dc.date.available","2018-11-07T09:17:45Z"],["dc.date.issued","2013"],["dc.description.abstract","Photochemically driven reactions involving unsaturated radicals produce a thick global layer of organic haze on Titan, Saturn's largest moon. The allyl radical self-reaction is an example for this type of chemistry and was examined at room temperature from an experimental and kinetic modelling perspective. The experiments were performed in a static reactor with a volume of 5 L under wall free conditions. The allyl radicals were produced from laser flash photolysis of three different precursors allyl bromide (C3H5Br), allyl chloride (C3H5Cl), and 1,5-hexadiene (CH2CH(CH2)(2)CHCH2) at 193 nm. Stable products were identified by their characteristic vibrational modes and quantified using FTIR spectroscopy. In addition to the (re-) combination pathway C3H5+C3H5 -> C6H10 we found at low pressures around 1 mbar the highest final product yields for allene and propene for the precursor C3H5Br. A kinetic analysis indicates that the end product formation is influenced by specific reaction kinetics of photochemically activated allyl radicals. Above 10 mbar the (re-) combination pathway becomes dominant. These findings exemplify the specificities of reaction kinetics involving chemically activated species, which for certain conditions cannot be simply deduced from combustion kinetics or atmospheric chemistry on Earth."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2013"],["dc.identifier.doi","10.3390/molecules181113608"],["dc.identifier.fs","600601"],["dc.identifier.isi","000330311500033"],["dc.identifier.pmid","24192913"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/9485"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/28241"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Mdpi Ag"],["dc.relation.issn","1420-3049"],["dc.rights.access","openAccess"],["dc.title","Pressure Dependent Product Formation in the Photochemically Initiated Allyl plus Allyl Reaction"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","9054"],["dc.bibliographiccitation.issue","25"],["dc.bibliographiccitation.journal","Physical Chemistry, Chemical Physics"],["dc.bibliographiccitation.lastpage","9057"],["dc.bibliographiccitation.volume","14"],["dc.contributor.author","Forck, Richard M."],["dc.contributor.author","Dieterich, Johannes M."],["dc.contributor.author","Pradzynski, Christoph C."],["dc.contributor.author","Huchting, Anna L."],["dc.contributor.author","Mata, Ricardo A."],["dc.contributor.author","Zeuch, Thomas"],["dc.date.accessioned","2018-11-07T09:15:19Z"],["dc.date.accessioned","2020-05-12T12:31:49Z"],["dc.date.available","2018-11-07T09:15:19Z"],["dc.date.available","2020-05-12T12:31:49Z"],["dc.date.issued","2012"],["dc.description.abstract","The structures of sodium doped water trimers are characterized on the basis of their infrared action spectra in the OH- stretching region and a global optimization approach to identify the lowest energy minima. The most stable structure is an open ring with two contacts of terminal water molecules to the Na atom. This structure explains the dominating feature in the IR depletion spectrum around 3410 cm(-1). Three additional isomer classes were found in an energy window of 12 kJ mol (-1) with vertical ionization energies ranging from similar to 3.83 eV to similar to 4.36 eV. These structures show different hydrogen bonding and sodium coordination patterns and are identified by specific spectral features in the IR spectra. The significant abundance of closed rings with an external Na atom, resembling the undoped water trimer, suggests that for larger clusters the picture of the sodium atom being situated on the cluster surface seems adequate."],["dc.description.sponsorship","DFG [GRK782, ZE 890-1-1]"],["dc.identifier.doi","10.1039/c2cp41066d"],["dc.identifier.isi","000305006200033"],["dc.identifier.pmid","22641269"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10229"],["dc.identifier.scopus","2-s2.0-84862275370"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/27651"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/65225"],["dc.identifier.url","http://www.scopus.com/inward/record.url?eid=2-s2.0-84862275370&partnerID=MN8TOARS"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation.eissn","1463-9084"],["dc.relation.issn","1463-9076"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Structural diversity in sodium doped water trimers"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]