Uptake of methanol on mixed HNO3/H2O clusters: An absolute pickup cross section

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388955%3A_____%2F18%3A00489300" target="_blank" >RIV/61388955:_____/18:00489300 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1063/1.5021471" target="_blank" >http://dx.doi.org/10.1063/1.5021471</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1063/1.5021471" target="_blank" >10.1063/1.5021471</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Uptake of methanol on mixed HNO3/H2O clusters: An absolute pickup cross section

Popis výsledku v původním jazyce

The uptake of atmospheric oxidized organics on acid clusters is relevant for atmospheric new particle formation. We investigate the pickup of methanol (CH3OH) on mixed nitric acid-water clusters (HNO3)(M)(H2O)(N) by a combination of mass spectrometry and cluster velocity measurements in a molecular beam. The mass spectra of the mixed clusters exhibit (HNO3)(m)(H2O)(n)H+ series with m = 0-3 and n = 0-12. In addition, CH3OH center dot(HNO3)(m)(H2O)(n)H+ series with very similar patterns appear in the spectra after the methanol pickup. The velocity measurements prove that the undoped (HNO3)(m)(H2O)(n)H+ mass peaks in the pickup spectra originate from the neutral (HNO3)(M)(H2O)(N) clusters which have not picked up any CH3OH molecule, i.e., methanol has not evaporated upon the ionization. Thus the fraction of the doped clusters can be determined and the mean pickup cross section can be estimated, yielding (sigma) over bar (s) approximate to 20 angstrom(2). This is compared to the lower estimate of the mean geometrical cross section (sigma) over bar (g) approximate to 60 angstrom(2) obtained from the theoretical cluster geometries. Thus the ´size´ of the cluster corresponding to the methanol pickup is at least 3-times smaller than its geometrical size. We have introduced a method which can yield the absolute pickup cross sections relevant to the generation and growth of atmospheric aerosols, as illustrated in the example of methanol and nitric acid clusters. Published by AIP Publishing.

Název v anglickém jazyce

Uptake of methanol on mixed HNO3/H2O clusters: An absolute pickup cross section

Popis výsledku anglicky

The uptake of atmospheric oxidized organics on acid clusters is relevant for atmospheric new particle formation. We investigate the pickup of methanol (CH3OH) on mixed nitric acid-water clusters (HNO3)(M)(H2O)(N) by a combination of mass spectrometry and cluster velocity measurements in a molecular beam. The mass spectra of the mixed clusters exhibit (HNO3)(m)(H2O)(n)H+ series with m = 0-3 and n = 0-12. In addition, CH3OH center dot(HNO3)(m)(H2O)(n)H+ series with very similar patterns appear in the spectra after the methanol pickup. The velocity measurements prove that the undoped (HNO3)(m)(H2O)(n)H+ mass peaks in the pickup spectra originate from the neutral (HNO3)(M)(H2O)(N) clusters which have not picked up any CH3OH molecule, i.e., methanol has not evaporated upon the ionization. Thus the fraction of the doped clusters can be determined and the mean pickup cross section can be estimated, yielding (sigma) over bar (s) approximate to 20 angstrom(2). This is compared to the lower estimate of the mean geometrical cross section (sigma) over bar (g) approximate to 60 angstrom(2) obtained from the theoretical cluster geometries. Thus the ´size´ of the cluster corresponding to the methanol pickup is at least 3-times smaller than its geometrical size. We have introduced a method which can yield the absolute pickup cross sections relevant to the generation and growth of atmospheric aerosols, as illustrated in the example of methanol and nitric acid clusters. Published by AIP Publishing.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

<a href="/cs/project/GA17-04068S" target="_blank" >GA17-04068S: Molekulové klastry jako nano-reaktory pro chemii řízenou fotony a elektrony</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Chemical Physics

ISSN

0021-9606

e-ISSN

—

Svazek periodika

148

Číslo periodika v rámci svazku

15

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

7

Strana od-do

—

Kód UT WoS článku

000430485700005

EID výsledku v databázi Scopus

2-s2.0-85045555226