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Title: Ion-molecule interactions enable unexpected phase transitions in organic-inorganic aerosol
Atmospheric aerosol particles are commonly complex, aqueous organic-inorganic mixtures, and accurately predicting the properties of these particles is essential for air quality and climate projections. The prevailing assumption is that aqueous organic-inorganic aerosols exist predominately with liquid properties and that the hygroscopic inorganic fraction lowers aerosol viscosity relative to the organic fraction alone. Here, in contrast to those assumptions, we demonstrate that increasing inorganic fraction can increase aerosol viscosity (relative to predictions) and enable a humidity-dependent gel phase transition through cooperative ion-molecule interactions that give rise to long-range networks of atmospherically relevant low-mass oxygenated organic molecules (180 to 310 Da) and divalent inorganic ions. This supramolecular, ion-molecule effect can drastically influence the phase and physical properties of organic-inorganic aerosol and suggests that aerosol may be (semi)solid under more conditions than currently predicted. These observations, thus, have implications for air quality and climate that are not fully represented in atmospheric models.  more » « less
Award ID(s):
1925208
PAR ID:
10230151
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
6
Issue:
47
ISSN:
2375-2548
Page Range / eLocation ID:
eabb5643
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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