Quantum chemical modeling of organic enhanced atmospheric nucleation: A critical review

Abstract

Aerosol particles are important for our global climate, but the mechanisms and especially the relative importance of various vapors for new particles formation (NPF) remain uncertain. Quantum chemical (QC) studies on organic enhanced nucleation has for the past couple of decades attracted immense attention, but very little remains known about the exact organic compounds that potentially are important for NPF. Here we comprehensively review the QC literature on atmospheric cluster formation involving organic compounds. We outline the potential cluster systems that should be further investigated. Cluster formation involving complex multi‐functional organic accretion products warrant further investigations, but such systems are out of reach with currently applied methodologies. We suggest a “cluster of functional groups” approach to address this issue, which will allow for the identification of the potential structure of organic compounds that are involved in atmospheric NPF.This article is categorized under: Theoretical and Physical Chemistry > Reaction Dynamics and Kinetics Software > Quantum Chemistry Theoretical and Physical Chemistry > Thermochemistry Molecular and Statistical Mechanics > Molecular Interactions

Prebiotic dimer and trimer peptide formation in gas-phase atmospheric nanoclusters of water

“…Finally, we note that the largest contributor to Δ G is the electronic energy component, so that the errors in relying on DFT for structures and energies versus using a CCSD(T)/CBS//DFT approach are most likely larger than the error in the entropies and thermal energy factors. 72…”

The driving effects of common atmospheric molecules for formation of clusters: the case of sulfuric acid, formic acid, hydrochloric acid, ammonia, and dimethylamine

“…Structures that don't contain HCl were taken from our previous papers, 66,73,88 and more explanation of our methodologies can be found in our recent review. 74 Once all the G ° values were calculated for the individual clusters, the Δ G ° values of binding were calculated as follows:…”

“…Three caveats on our methodology are important to note. 74 First, no search routine can ensure that all of the potential energy surface (PES) for these clusters has been exhaustively explored, so we may have missed the lowest Gibbs free energy structure. Second, in the funnel methodology (Fig.…”

“…5,6 Many studies have demonstrated the driving effect of sulfuric acid (SA) in forming prenucleation clusters, especially in the presence of other atmospheric acids and bases. 7–74 Hydrochloric acid (HCl), on the other hand, has not been as well studied for its potential role in the formation of pre-nucleation clusters. 75 It is estimated that 85% of the HCl in the atmosphere is produced from acid displacement of sea salt aerosols.…”

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