The Hydration of Trifluoroacetic Acid from 0 K to 298 K
ACS Citation
Smith, W. J., Glick, C. S., Shields, G.C. The Hydration of Trifluoroacetic Acid from 0 K to 298 K, J. Phys. Chem. A 2026, 130 (4) 927-935. DOI: 10.1021/acs.jpca.5c08151.
Version of Record
Abstract
Trifluoroacetic acid (TFA), the most atmospherically abundant perfluorocarbocylic acid, is a molecule of increasing environmental and biological significance. In this paper, we examine TFA’s role in new particle formation (NPF), a critical yet lesser-understood step in cloud formation in which aerosols that act as cloud condensation nuclei are formed. We used conformational sampling to find low-energy structures for TFA-nH2O (n =1−8) clusters and determined accurate DLPNO−CCSD(T)/haug-cc-pV5Z//ωB97X-D/6−31++G** enthalpies at 0 K and Gibbs free energies at 216.65, 273.15, and 298.15 K. Then, atmospheric concentrations were determined at relevant atmospheric temperatures. Rotational constants for the lowest energy n = 1−3 structures corroborate existing microwave spectroscopic data, validating our methodology. Additionally, spectroscopic properties for n = 4−8 structures were identified for comparison with future experimental findings. All lowest energy structures were found to have neutral, rather than ion-pair monomers. Near Earth's surface, we predict significant concentrations of n = 1−2 clusters (2.06 Å~ 105 molecules cm−3 and 1.13 Å~ 104, respectively); however, the absence of larger clusters indicates that TFA likely serves a negligible role in NPF.
Source Name
The Journal of Physical Chemistry A
Publication Date
1-20-2026
Volume
130
Issue
4
Page(s)
927-935
Document Type
Citation
Citation Type
Article