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. (C) 2014 Elsevier B.V. All rights reserved.