1. RH12, 70th International Symposium on Molecular Spectroscopy
THE CP-FTMW SPECTROSCOPY AND ASSIGNMENT OF THE MONO- AND DIHYDRATE COMPLEXES OF PERFLUOROPROPIONIC ACID
G. S. Grubbs II, Daniel A. Obenchain, Derek S. Frank, Stewart E. Novick, S. A. Cooke, Agapito Serrato III, and Wei Lin
RH12, 70th International Symposium on Molecular Spectroscopy
June 22-26, 2015, Urbana, IL, USA

2. Motivation a
Perfluorinated Carboxylic Acids (PFCAs) are commonly used as surfactants
Have been detected in groundwater, lake water, wildlife, and human blood serum1
Wei came to Wesleyan with an interest in studying these interactions
1. B. F. Scott, C. A. Moody, C. Specer, J. M. Small, D. C. G. Muir, S. A. Mabury. Environ. Sci. Technol. 40 (2006) 6405.

3. Experiment
Free Induction Decay Collected, Amplified and Digitized on a 40 GS/s oscilloscope
Linear Frequency Sweep 0 – x - “Chirp”
ν +/- x is amplified, pulsed and broadcast
Center Frequency, ν, between 8-18 GHz
Excitation interacts with the molecules
To Diff. Pump

4. Experimental Details
97% PFPA purchased from Sigma-AldrichTM without further purification
1.5 atm Ar bubbled through sample ~40 cm upstream from Parker® Series 9 solenoid valve
8 μs chirps of 2 GHz regions
30,000 FID averages
MHz

5. Quantum Chemical Calculations

6. Results H2O-PFPA

7. Results (H2O)2-PFPA

8. Results (Comparison)

9. Results

10. Hydrating PFPA

11. Pcc Arguments
H2O-TFA: B. Ouyang, T. G. Starkey, and B. J. Howard. J. Phys. Chem. A. 111 (2007) 6165.
H2O-PFBA: J. Thomas, A. Serrato, III, W. Lin, W. Jäger, Y. Xu. Chem. Eur. J. 20 (2014) 6148.

12. Conclusions
PFPA Hydration occurs in plane with the carboxylic acid group with hydrogens out of plane
No tunneling
Structure explained with Pcc arguments
Submitted to J. Phys. Chem. A

13. Acknowledgements WL Welch Foundation SEN NSF Grant
GSGII Missouri Research Board Grant
Bob Bohn and Pete Pringle useful discussions