A Study of the Monohydrate and Dihydrate Complexes of Perfluoropropionic Acid using Chirped-Pulse Fourier Transform Microwave (CP-FTMW) Spectroscopy


This work reports the first known spectroscopic observation of the monohydrate and dihydrate complexes of perfluoropropionic acid (PFPA). The spectra have been observed using a chirped-pulse Fourier transform microwave (CP-FTMW) spectrometer in the 7750 to 14250 MHz region. The structures of the species have been confirmed with the aid of ab initio quantum chemical calculations. Rotational constants A, B, and C have been determined and reported for both species along with centrifugal distortion constants ΔJ, ΔJK, ΔK, δJ, δK for H2O-PFPA and ΔJ, ΔJK and δJ for (H2O)2-PFPA. Effects due to large amplitude motions were not observable in these experiments. Structures of the complexes have been determined using a combination of experimental second moment values and ab initio results. The complexation of the -OH of one or two water molecules has been found to occur in the plane of the carboxylic acid group forming a six- or eight-member ring.



Research Center/Lab(s)

Center for High Performance Computing Research

Keywords and Phrases

Calculations; Chirp Modulation; Complexation; Molecules; Quantum Chemistry; Spectrometers; Ab Initio Quantum Chemical Calculations; Carboxylic Acid Groups; Centrifugal Distortion Constants; Large-Amplitude Motion; Perfluoropropionic Acids; Rotational Constants; Second Moments; Water Molecule; Microwave Spectroscopy

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Article - Journal

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© 2015 American Chemical Society (ACS), All rights reserved.

Publication Date

01 Jan 2015