%0 Journal Article %1 Walser:2008p4084 %A Walser, Maggie L %A Desyaterik, Yury %A Laskin, Julia %A Laskin, Alexander %A Nizkorodov, Sergey A %D 2008 %J Physical Chemistry Chemical Physics %K Aerosols, Air-Pollution, Alpha-Pinene, Atlanta Atmospheric Biogenic Chemical-Composition, Experiment, Formation, Gas-Phase Hydrocarbons Molecular-Weight, Oh Ozone, Radical Reactions, Supersite %N 7 %P 1009--1022 %R 10.1039/b712620d %T High-resolution mass spectrometric analysis of secondary organic aerosol produced by ozonation of limonene %U http://www.rsc.org/publishing/journals/CP/article.asp?doi=b712620d %V 10 %X Chemical composition of secondary organic aerosol (SOA) formed from the ozone-initiated oxidation of limonene is characterized by high-resolution electrospray ionization mass spectrometry in both positive and negative ion modes. The mass spectra reveal a large number of both monomeric (m/z < 300) and oligomeric (m/z > 300) condensed products of oxidation. A combination of high resolving power (m/Delta m similar to 60000) and Kendrick mass defect analysis makes it possible to unambiguously determine the molecular composition of hundreds of individual compounds in SOA samples. Van Krevelen analysis shows that the SOA compounds are heavily oxidized, with average O:C ratios of 0.43 and 0.50 determined from the positive and negative ion mode spectra, respectively. A possible reaction mechanism for the formation of the first generation SOA molecular components is considered. The discussed mechanism includes known isomerization and addition reactions of the carbonyl oxide intermediates generated during the ozonation of limonene. In addition, it includes isomerization and decomposition pathways for alkoxy radicals resulting from unimolecular decomposition of carbonyl oxides that have been disregarded by previous studies. The isomerization reactions yield numerous products with a progressively increasing number of alcohol and carbonyl groups, whereas C-C bond scission reactions in alkoxy radicals shorten the carbon chain. Together these reactions yield a large number of isomeric products with broadly distributed masses. A qualitative agreement is found between the number and degree of oxidation of the predicted and measured reaction products in the monomer product range.

@article{Walser:2008p4084, abstract = {Chemical composition of secondary organic aerosol (SOA) formed from the ozone-initiated oxidation of limonene is characterized by high-resolution electrospray ionization mass spectrometry in both positive and negative ion modes. The mass spectra reveal a large number of both monomeric (m/z < 300) and oligomeric (m/z > 300) condensed products of oxidation. A combination of high resolving power (m/Delta m similar to 60000) and Kendrick mass defect analysis makes it possible to unambiguously determine the molecular composition of hundreds of individual compounds in SOA samples. Van Krevelen analysis shows that the SOA compounds are heavily oxidized, with average O:C ratios of 0.43 and 0.50 determined from the positive and negative ion mode spectra, respectively. A possible reaction mechanism for the formation of the first generation SOA molecular components is considered. The discussed mechanism includes known isomerization and addition reactions of the carbonyl oxide intermediates generated during the ozonation of limonene. In addition, it includes isomerization and decomposition pathways for alkoxy radicals resulting from unimolecular decomposition of carbonyl oxides that have been disregarded by previous studies. The isomerization reactions yield numerous products with a progressively increasing number of alcohol and carbonyl groups, whereas C-C bond scission reactions in alkoxy radicals shorten the carbon chain. Together these reactions yield a large number of isomeric products with broadly distributed masses. A qualitative agreement is found between the number and degree of oxidation of the predicted and measured reaction products in the monomer product range.}, added-at = {2010-06-22T19:38:37.000+0200}, affiliation = {Univ Calif Irvine, Dept Chem, Irvine, CA 92617 USA}, author = {Walser, Maggie L and Desyaterik, Yury and Laskin, Julia and Laskin, Alexander and Nizkorodov, Sergey A}, biburl = {https://www.bibsonomy.org/bibtex/2589b33a96fa2ab978d384b0481f8dd60/gsmith}, date-added = {2010-06-10 10:27:07 -0400}, date-modified = {2010-06-10 10:27:07 -0400}, doi = {10.1039/b712620d}, interhash = {e4a73890eb690ba75dd870b49d9245ff}, intrahash = {589b33a96fa2ab978d384b0481f8dd60}, journal = {Physical Chemistry Chemical Physics}, keywords = {Aerosols, Air-Pollution, Alpha-Pinene, Atlanta Atmospheric Biogenic Chemical-Composition, Experiment, Formation, Gas-Phase Hydrocarbons Molecular-Weight, Oh Ozone, Radical Reactions, Supersite}, language = {English}, local-url = {file://localhost/Users/geoffreysmith/Documents/Papers/Physical%20Chemistry%20Chemical%20Physics/2008/Physical%20Chemistry%20Chemical%20Physics,%2010,%201009-1022%202008.pdf}, month = Jan, number = 7, pages = {1009--1022}, pmid = {000253013800011}, rating = {0}, timestamp = {2010-06-22T19:38:53.000+0200}, title = {High-resolution mass spectrometric analysis of secondary organic aerosol produced by ozonation of limonene}, uri = {papers://E88B624E-D406-46FF-9D95-BB9C1AAE3FDC/Paper/p4084}, url = {http://www.rsc.org/publishing/journals/CP/article.asp?doi=b712620d}, volume = 10, year = 2008 }