Atmospheric clusters to nanoparticles: Recent progress and challenges in closing the gap in chemical composition

A predictive model for salt nanoparticle formation using heterodimer stability calculations

“…However, for pK a , TMAO salts seem to deviate drastically from the trend. Indeed, this is most likely because TMAO is more able to be stabilized by water molecules in the bulk aqueous phase and its proton exchange in the gas phase is not well represented by pK a (Myllys et al, 2021). Otherwise, the trend of pK a matches up well with that of GA.…”

“…Atmospheric aerosol particles represent the largest uncertainty in our understanding of global climate through their participation in cloud formation and the absorption and scattering of radiation (Kerminen et al, 2005;Kuang et al, 2009;Lohmann and Feichter, 2005;Merikanto et al, 2009;Spracklen et al, 2008). In particular, particle formation by nucleation is still not well understood and is difficult to represent in models (Kerminen et al, 2018).…”

“…This nucleation pathway is particularly dominant in urban environments, where anthropogenic sources for acidic and basic gases are abundant (Ge et al, 2011;Kirkby et al, 2011;Qiu and Zhang, 2013;Weber et al, 1996;Wang et al, 2020). Although sulfuric acid (H 2 SO 4 , SA) is most commonly associated with atmospheric nucleation (Ball et al, 1999;Bzdek et al, 2012;Kirkby et al, 2011;Angelino et al, 2001;Weber et al, 1995), nitric acid (HNO 3 , NA) and methanesulfonic acid (CH 3 SO 3 H, MSA) have been also observed to be participants and may also play important roles in the initial stages of cluster growth (Afpel et al, 1979;Barsanti et al, 2009;Mäkelä et al, 2001;Smith S. Chee et al: A predictive model for salt nanoparticle formation et al, 2004Weber et al, 1995), the latter of which we shall refer to henceforth as new particle formation (NPF). Ammonia is the most abundant base in the atmosphere and its reaction with sulfuric acid has been well studied (Bzdek et al, 2010;Glasoe et al, 2015;Weber et al, 1996).…”

“…Recently, computational efforts have focused on accurately representing the formation and growth of acid-base clusters (Smith et al, 2021). Myllys et al (2016a) investigated the accuracy of the domain local pair natural orbital coupled cluster (DLPNO-CCSD(T)) method and found that it allows for the modeling of up to 10 molecules in a cluster, which had not been previously feasible with other highly accurate methods.…”

Real-time monitoring of aerosol particle formation from sulfuric acid vapor at elevated concentrations and temperatures

“…The DLPNO-CCSD(T 0 )/aug-cc-pVTZ// ω B97X-D/6-31++G(d,p) level of theory has been shown to yield low errors compared to higher-level methods 32,33 and is in general recommended for modeling atmospheric molecular clusters. 34,35 We carefully checked that the same cluster configuration was the global free energy minimum across all the studied temperatures.…”