Title: | MICROWAVE SPECTRUM OF THE METHANESULFONIC ACID – WATER COMPLEX |
Author(s): | Huff, Anna |
Contributor(s): | Leopold, Kenneth R.; Love, Nathan |
Subject(s): | Small molecules |
Abstract: | The methanesulfonic acid water - complex (CH$_{3}$SO$_{3}$H-H$_{2}$O) has been observed using pulse-nozzle Fourier transform microwave spectroscopy. The rotational spectra for the CH$_{3}$SO$_{3}$H-D$_{2}$O and CH$_{3}$SO$_{3}$D-D$_{2}$O isotopologues have also been obtained and analyzed. DFT calculations predict the two lowest energy conformers of CH$_{3}$SO$_{3}$H-H$_{2}$O to form a strong hydrogen bond between the water molecule with the acidic proton and a second, longer hydrogen bond with one of the S=O bonds to form the 6-membered ring-like structure that is typical of oxyacid monohydrates. The observed rotational constants and isotope shifts are in best agreement with those predicted for the global minimum structure of CH$_{3}$SO$_{3}$H-H$_{2}$O, where the unbound H$_{2}$O hydrogen atom is oriented away from the methyl group. In contrast to the triflic acid monohydrate (CF$_{3}$SO$_{3}$H-H$_{2}$O) spectrum, there was no evidence of a pair of tunneling states arising from internal motion of the water. Additionally, A and E internal rotor states were not resolvable in the observed spectrum, consistent with the predicted high barrier for methyl group internal rotation (\textit{V}$_{3}$=1000 \wn). |
Issue Date: | 24-Jun-20 |
Publisher: | International Symposium on Molecular Spectroscopy |
Citation Info: | APS |
Genre: | CONFERENCE PAPER/PRESENTATION |
Type: | Text |
Language: | English |
URI: | http://hdl.handle.net/2142/107421 |
Date Available in IDEALS: | 2020-06-26 |