Files in this item

FilesDescriptionFormat

application/vnd.openxmlformats-officedocument.presentationml.presentation

application/vnd.openxmlformats-officedocument.presentationml.presentation1408913.pptx (5MB)
PresentationMicrosoft PowerPoint 2007

application/pdf

application/pdf3839.pdf (18kB)
AbstractPDF

Description

Title:MICROWAVE SPECTRUM OF A SUPERACID AND ITS MONOHYDRATE: TUNNELING AND LARGE AMPLITUDE MOTION IN CF3SO2OH AND CF3SO2OH-H2O
Author(s):Huff, Anna
Contributor(s):Leopold, Kenneth R.; Smith, CJ ; Love, Nathan
Subject(s):Mini-symposium: Non-covalent Interactions
Abstract:The triflic acid monomer (CF$_{3}$SO$_{2}$OH) and its 1:1 complex with water (CF$_{3}$SO$_{2}$OH-H$_{2}$O) have been observed by chirped-pulse and cavity Fourier transform microwave spectroscopy. A pair of tunneling states was identified in the rotational spectra for both species. For CF$_{3}$SO$_{2}$OH, the assignment of \textit{b}-type spectra led to the direct measurement and experimental determination of the tunneling energy ($\Delta$E = 52.96704(90) MHz). M06-2X/6-311++G(3df,3pd) calculations predict a 2.8 kcal/mol barrier for the tunneling motion of the hydroxyl proton rotating around the S-O bond through a transition state in which the O-H is oriented \textit{anti} with respect to the CF$_{3}$ group. A complete $360^{\circ}$ scan of the hydroxyl proton around the S-O bond shows an additional transition state in the \textit{syn} orientation resulting in a 6.2 kcal/mol barrier. In the CF$_{3}$SO$_{2}$OH-H$_{2}$O complex, spectral doublets were observed with an approximate 3:1 intensity ratio indicative of an equivalent exchange of the protons in H$_{2}$O resulting from rotation about its C$_{2}$ axis. The proposed water motion is further supported by the quenching of the spectral pairs for the asymmetrically deuterated CF$_{3}$SO$_{2}$OH-DOH complex. Despite the strong acidity of triflic acid, no evidence of protonation of the water was observed.
Issue Date:2019-06-19
Publisher:International Symposium on Molecular Spectroscopy
Genre:Conference Paper / Presentation
Type:Text
Language:English
URI:http://hdl.handle.net/2142/104294
DOI:10.15278/isms.2019.WB07
Rights Information:Copyright 2019 Anna Huff
Date Available in IDEALS:2019-07-15
2020-01-25


This item appears in the following Collection(s)

Item Statistics