Rotational Spectra, Conformational Structures and Dipole Moments of Thiodiglycol by Jet-Cooled FTMW and Ab Initio Calculations

Published

May 1, 2004

Author(s)

L H. Xu, Q Liu, R D. Suenram, Francis J. Lovas, Angela R. Hight Walker, J O. Jensen, A C. Samuels

Abstract

The rotational spectra of three low-energy conformers of thiodiglycol (TDG) (HOCH2CH2SCH2CH2OH) have been measured in a molecular beam using a pulsed-nozzle Fourier-transform microwave spectrometer. To determine the likely conformational structures with ab initio approach, conformational structures of 2-(ethylthio)ethanol (HOEES) (CH3CH2CH2SCH2OH) were used as starting points together with the consideration of possible hydrogen bonding in TDG. Three lower energy conformers have been found for TDG at the MP2=Full/6 311G** level and ab initio results agree nicely with experimentally determined rotational constants. In addition, Stark measurements were performed for two of the three conformers for dipole moment determinations, adding to our confidence of the conformational structure matches between experimental observations and ab initio calculations. Of the three lower energy conformers, one displays a compact folded-like structure with strong hydrogen bonding between the two hydroxyl groups and the central sulfide atom. Two other conformers have relatively open chain-like structures with hydrogen bonding between each of the hydroxyl groups to the central sulfur atom, of which one has near pure b-type dipole moment according to the ab initio results.

Citation

Journal of Molecular Spectroscopy

Volume

228

Pub Type

Journals

Keywords

ab initio calculations, dipole moment, microwave spectrum, molecular structure, rotational spectrum, thiodiglycol

Citation

Xu, L. , Liu, Q. , Suenram, R. , Lovas, F. , Hight Walker, A. , Jensen, J. and Samuels, A. (2004), Rotational Spectra, Conformational Structures and Dipole Moments of Thiodiglycol by Jet-Cooled FTMW and Ab Initio Calculations, Journal of Molecular Spectroscopy (Accessed October 11, 2025)