Enhancement in the production of nucleating clusters due to dimethylamine and large uncertainties in the thermochemistry of amine-enhanced nucleation

In the present Letter, the enhancing effect of dimethylamine (DMA) on the production of stable H2SO4–H2O clusters have been studied using the Density Functional Theory (DFT). It has been pointed out that the DMA concentrations of 1–10 ppt are needed in order to achieve a considerable enhancement in production of sulfuric acid–water clusters under typical atmospheric conditions and that the ambient RH plays a significant role at the early stages of the gas-to cluster conversion in the ternary DMA–H2SO4–H2O vapour mixtures. Large uncertainties in the thermochemistry of amine-enhanced nucleation have been pointed out and discussed.