Clusteromics I: Principles, Protocols, and Applications to Sulfuric Acid–Base Cluster Formation

Synergistic effects between different bases can greatly enhance atmospheric sulfuric acid (SA)-base cluster formation. However, only the synergy between two base components has previously been investigated. Here, we extend this concept to three bases by studying large atmospherically relevant (SA)3(base)3 clusters, with the bases ammonia (A), methylamine (MA), dimethylamine (DMA), trimethylamine (TMA) and ethylenediamine (EDA). Using density functional theory—ωB97X-D/6-31++G(d,p)—we calculate the cluster structures and vibrational frequencies. The thermochemical parameters are calculated at 29,815 K and 1 atm, using the quasi-harmonic approximation. The binding energies of the clusters are calculated using high level DLPNO-CCSD(T0)/aug-cc-pVTZ. We find that the cluster stability in general depends on the basicity of the constituent bases, with some noteworthy additional guidelines: DMA enhances the cluster stability, TMA decreases the cluster stability and there is high synergy between DMA and EDA. Based on our calculations, we find it highly likely that three, or potentially more, different bases, are involved in the growth pathways of sulfuric acid-base clusters.

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Chemical ionization of clusters formed from sulfuric acid and dimethylamine or diamines

10.5194/acp-2016-492 ◽

2016 ◽

Author(s):

Coty N. Jen ◽

Jun Zhao ◽

Peter H. McMurry ◽

David R. Hanson

Keyword(s):

Sulfuric Acid ◽

Chemical Ionization ◽

Flow Reactor ◽

Cluster Formation ◽

Mass Spectrometers ◽

Model Calculations ◽

Molecule Reaction ◽

Base Content ◽

Atmospheric Nucleation ◽

High Base

Abstract. Chemical ionization (CI) mass spectrometers are used to study atmospheric nucleation by detecting clusters produced by reactions of sulfuric acid and various basic gases. These instruments typically use nitrate to deprotonate and thus chemically ionize the clusters. In this study, we compare cluster concentrations measured using either nitrate or acetate. Clusters were formed in a flow reactor from vapors of sulfuric acid and dimethylamine, ethylene diamine, tetramethylethylene diamine, or butanediamine (also known as putrescine). These comparisons show that nitrate is unable to chemically ionize clusters with high base content. In addition, we vary the ion-molecule reaction time to probe ion processes which include proton-transfer, ion-molecule clustering, and decomposition of ions. Ion decomposition upon deprotonation by acetate/nitrate was observed. More studies are needed to quantify to what extent ion decomposition affects observed cluster content and concentrations, especially those chemically ionized with acetate since it deprotonates more types of clusters than nitrate. Model calculations of the neutral and ion cluster formation pathways are also presented to better identify the cluster types that are not efficiently deprotonated by nitrate. Comparison of model and measured clusters indicate that sulfuric acid dimer with two diamines and sulfuric acid trimer with two or more base molecules are not efficiently chemical ionized by nitrate. We conclude that acetate CI provides better information on cluster abundancies and their base content than nitrate CI.

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A Monte Carlo approach for determining cluster evaporation rates from concentration measurements

10.5194/acp-2016-168 ◽

2016 ◽

Author(s):

Oona Kupiainen-Määttä

Keyword(s):

Experimental Data ◽

Monte Carlo ◽

Markov Chain ◽

Sulfuric Acid ◽

Markov Chain Monte Carlo ◽

Mass Spectrometer ◽

Large Fraction ◽

Cluster Formation ◽

Unknown Parameters ◽

Ammonia Clusters

Abstract. Evaporation rates of small negatively charged sulfuric acid–ammonia clusters are determined by combining detailed cluster formation simulations with cluster distributions measured at CLOUD. The analysis is performed by varying the evaporation rates with Markov chain Monte Carlo (MCMC), running cluster formation simulations with each new set of evaporation rates and comparing the obtained cluster distributions to the measurements. In a second set of simulations, the fragmentation of clusters in the mass spectrometer due to energetic collisions is studied by treating also the fragmentation probabilities as unknown parameters and varying them with MCMC. This second set of simulations results in a better fit to the experimental data, suggesting that a large fraction of the observed HSO4− and HSO4− ⋅ H2SO4 signals may result from fragmentation of larger clusters, most importantly the HSO4− ⋅ (H2SO4)2 trimer.

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Non-peripherally alkylamino-substituted phthalocyanines: Synthesis, spectral, photophysical and acid-base properties

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s108842461950024x ◽

2019 ◽

Vol 23 (04n05) ◽

pp. 427-436 ◽

Cited By ~ 3

Author(s):

Lucia Kociscakova ◽

Merve Ipek Senipek ◽

Petr Zimcik ◽

Veronika Novakova

Keyword(s):

Sulfuric Acid ◽

Trifluoroacetic Acid ◽

Fluorescence Emission ◽

Optimal Conditions ◽

Oxygen Production ◽

Acid Base ◽

Metal Free ◽

Near Ir ◽

Zinc Phthalocyanines ◽

Photophysical Study

Non-peripherally substituted metal-free and zinc phthalocyanines (Pcs) bearing four diethylamino groups and four Br atoms were prepared. Optimal conditions for synthesis of corresponding precursor ([Formula: see text] 3-bromo-6-(diethylamino)phthalonitrile) either by nucleophilic substitution or by Buchwald–Hartwig coupling were studied. Noteworthy, 3,6-bis(diethylamino)phthalonitrile was also formed, nevertheless only at low yield (typically below 1%) and all attempts for its cyclotetramerization failed. Q bands of prepared Pcs were strongly red shifted up to the near-IR region (769 and 800 nm in THF for zinc and metal-free Pc, respectively). Unusually large hypsochromic shifts of the Q bands, 130 and 80 nm for metal-free and zinc Pc, respectively, were observed upon treating these Pcs with trifluoroacetic acid, which was attributed to the protonation of non-peripheral amines. Treatment with sulfuric acid led to subsequent protonation on the azomethine nitrogens as well. Photophysical study revealed low fluorescence emission of both derivatives ([Formula: see text] <0.03, in THF) and efficient singlet oxygen production only for zinc Pc ([Formula: see text] 0.77 in THF and 0.60 in DMF).

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Neutral molecular cluster formation of sulfuric acid–dimethylamine observed in real time under atmospheric conditions

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1404853111 ◽

2014 ◽

Vol 111 (42) ◽

pp. 15019-15024 ◽

Cited By ~ 123

Author(s):

Andreas Kürten ◽

Tuija Jokinen ◽

Mario Simon ◽

Mikko Sipilä ◽

Nina Sarnela ◽

...

Keyword(s):

Sulfuric Acid ◽

Real Time ◽

Cluster Formation ◽

Molecular Cluster ◽

Atmospheric Conditions

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New Particle Formation Involving Charged Sulfuric Acid – Ammonia Clusters

10.5194/egusphere-egu2020-5152 ◽

2020 ◽

Author(s):

Vitus Besel ◽

Jakub Kubečka ◽

Theo Kurtén ◽

Hanna Vehkamäki

Keyword(s):

Sulfuric Acid ◽

Computational Study ◽

Cluster Formation ◽

Chem Phys ◽

Particle Formation ◽

Empirical Method ◽

Particle Nucleation ◽

New Particle Formation ◽

Charged Clusters ◽

Ammonia Clusters

<div> The bulk of aerosol particles in the atmosphere are formed by gas-to-particle nucleation (Merikanto et al., 2009). However, the exact process of single molecules forming cluster, which subsequently can grow into particles, remains largely unknown. Recently, sulfuric acid has been identified to play a key role in this new particle formation enhanced by other compounds such as organic acids (Zhang, 2010) or ammonia (Anttila et al., 2005). To identify the characteristics of cluster formation and nucleation involving sulfuric acid and ammonia in neutral, positive and negative modes, we conducted a computational study. We used a layered approach for configurational sampling of the molecular clusters starting from utilizing a genetic algorithm in order to explore the whole potential energy surface (PES) with all plausible geometrical minima, however, with very unreliable energies. The structures were further optimized with a semi-empirical method and, then, at the &#969;B97X-D DFT level of theory. After each step, the optimized geometries were filtered to obtain the global minimum configuration. Further, a high level of theory (DLPNO-CCSD(T)) was used for obtaining the electronic energies, in addition to performing DFT frequency analysis, to calculate the Gibbs free energies of formation. These were passed to the Atmospheric Cluster Dynamics Code (ACDC) (McGrath et al., 2012) for studying the evolution of cluster populations. We determined the global minima for the following sulfuric acid - ammonia clusters: (H2SO4)m(NH3)n with m=n, m=n+1 and n=m+1 for neutral clusters, (H2SO4)m(HSO4)&#8722;(NH3)n with m=n and n=m+1 for positively charged clusters, and (H2SO4)m(NH4)+(NH3)n with m=n and m=n+1 for negatively charged clusters. Further, we present the formation rates, steady state concentrations and fluxes of these clusters calculated using ACDC and discuss how a new configurational sampling procedure, more precise quantum chemistry methods and parameters, such as symmetry and a quasiharmonic approach, impact these ACDC results in comparison to previous studies. </div><div> References: J. Merikanto, D. V. Spracklen, G. W. Mann, S. J. Pickering, and K. S. Carslaw (2009). Atmos. Chem.&#160; Phys., 9, 8601-8616. R. Zhang (2010). Science, 328, 1366-1367. T. Anttila, H. Vehkam&#228;ki, I. Napari, M. Kulmala (2005). Boreal Env. Res., 10, 523. M.J. McGrath, T. Olenius, I.K. Ortega, V. Loukonen, P.&#160; Paasonen, T. Kurten, M. Kulmala (2012). Atmos. Chem. Phys., 12, 2355. </div>

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Chemical ionization of clusters formed from sulfuric acid and dimethylamine or diamines

Atmospheric Chemistry and Physics ◽

10.5194/acp-16-12513-2016 ◽

2016 ◽

Vol 16 (19) ◽

pp. 12513-12529 ◽

Cited By ~ 16

Author(s):

Coty N. Jen ◽

Jun Zhao ◽

Peter H. McMurry ◽

David R. Hanson

Keyword(s):

Sulfuric Acid ◽

Reaction Time ◽

Chemical Ionization ◽

Flow Reactor ◽

Cluster Formation ◽

Mass Spectrometers ◽

Molecule Reaction ◽

Base Content ◽

Atmospheric Nucleation ◽

High Base

Abstract. Chemical ionization (CI) mass spectrometers are used to study atmospheric nucleation by detecting clusters produced by reactions of sulfuric acid and various basic gases. These instruments typically use nitrate to deprotonate and thus chemically ionize the clusters. In this study, we compare cluster concentrations measured using either nitrate or acetate. Clusters were formed in a flow reactor from vapors of sulfuric acid and dimethylamine, ethylene diamine, tetramethylethylene diamine, or butanediamine (also known as putrescine). These comparisons show that nitrate is unable to chemically ionize clusters with high base content. In addition, we vary the ion–molecule reaction time to probe ion processes which include proton-transfer, ion–molecule clustering, and decomposition of ions. Ion decomposition upon deprotonation by acetate/nitrate was observed. More studies are needed to quantify to what extent ion decomposition affects observed cluster content and concentrations, especially those chemically ionized with acetate since it deprotonates more types of clusters than nitrate.Model calculations of the neutral and ion cluster formation pathways are also presented to better identify the cluster types that are not efficiently deprotonated by nitrate. Comparison of model and measured clusters indicate that sulfuric acid dimers with two diamines and sulfuric acid trimers with two or more base molecules are not efficiently chemical ionized by nitrate. We conclude that acetate CI provides better information on cluster abundancies and their base content than nitrate CI.

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Model for acid-base chemistry in nanoparticle growth (MABNAG)

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-13-7175-2013 ◽

2013 ◽

Vol 13 (3) ◽

pp. 7175-7222 ◽

Cited By ~ 1

Author(s):

T. Yli-Juuti ◽

K. Barsanti ◽

L. Hildebrandt Ruiz ◽

A.-J. Kieloaho ◽

U. Makkonen ◽

...

Keyword(s):

Particle Size ◽

Sulfuric Acid ◽

Gas Phase ◽

Organic Compounds ◽

Particle Growth ◽

Particle Phase ◽

Vapor Pressures ◽

Salt Formation ◽

Acid Base ◽

Nanoparticle Growth

Abstract. Climatic effects of newly-formed atmospheric secondary aerosol particles are to a large extent determined by their condensational growth rates. However, all the vapors condensing on atmospheric nanoparticles and growing them to climatically relevant sizes are not identified yet and the effects of particle phase processes on particle growth rates are poorly known. Besides sulfuric acid, organic compounds are known to contribute significantly to atmospheric nanoparticle growth. In this study a particle growth model MABNAG (Model for Acid-Base chemistry in NAnoparticle Growth) was developed to study the effect of salt formation on nanoparticle growth, which has been proposed as a potential mechanism lowering the equilibrium vapor pressures of organic compounds through dissociation in the particle phase and thus preventing their evaporation. MABNAG is a model for monodisperse aqueous particles and it couples dynamics of condensation to particle phase chemistry. Non-zero equilibrium vapor pressures, with both size and composition dependence, are considered for condensation. The model was applied for atmospherically relevant systems with sulfuric acid, one organic acid, ammonia, one amine and water in the gas phase allowed to condense on 3–20 nm particles. The effect of dissociation of the organic acid was found to be small under ambient conditions typical for a boreal forest site, but considerable for base-rich environments (gas phase concentrations of about 1010 cm−3 for the sum of the bases). The contribution of the bases to particle mass decreased as particle size increased, except at very high gas phase concentrations of the bases. The relative importance of amine versus ammonia did not change significantly as a function of particle size. While our results give a reasonable first estimate on the maximum contribution of salt formation to nanoparticle growth, further studies on, e.g. the thermodynamic properties of the atmospheric organics, concentrations of low-volatility organic acids and amines, along with studies investigating the applicability of thermodynamics for the smallest nanoparticles are needed to truly understand the acid-base chemistry of atmospheric nanoparticles.

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Methane sulfonic acid enhanced formation of molecular clusters of sulfuric acid and dimethyl amine

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-18679-2014 ◽

2014 ◽

Vol 14 (12) ◽

pp. 18679-18701

Author(s):

N. Bork ◽

J. Elm ◽

T. Olenius ◽

H. Vehkamäki

Keyword(s):

Sulfuric Acid ◽

Gas Phase ◽

Sulfonic Acid ◽

Cluster Formation ◽

Ab Initio Methods ◽

Coastal Regions ◽

Methane Sulfonic Acid ◽

Dimethyl Amine ◽

Order Of Magnitude ◽

Main Growth

Abstract. Over oceans and in coastal regions methane sulfonic acid (MSA) is present in substantial concentrations in aerosols and in the gas phase. We present an investigation of the effect of MSA on sulfuric acid and dimethyl amine (DMA) based cluster formation rates. From systematic conformational scans and well tested ab initio methods, we optimize structures of all MSAx (H2SO4)yDMAz clusters where x + y &leq; 3 and z &leq; 2. The resulting thermodynamic data is used in the Atmospheric Cluster Dynamics Code and the effect of MSA is evaluated by comparing ternary MSA-H2SO4-DMA cluster formation rates to binary H2SO4-DMA cluster formation rates. Within the range of atmospherically relevant MSA concentrations, we find that MSA may increase cluster formation rates by up to one order of magnitude, although typically, the increase will be less than 300% at 258 K, less than 100% at 278 K and less than 15% at 298 K. The results are rationalized by a detailed analysis of the the main growth paths of the clusters. We find that MSA enhanced clustering involves clusters containing one MSA molecule, while clusters containing more than one MSA molecule do not contribute significantly to the growth.

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