Extension of 2-Ethoxyethanol Rotational Spectroscopy and Its Search in the Interstellar Medium
- 1Univ. Lille
- 2Massachusetts Institute of Technology
- 3National Radio Astronomy Observatory
Abstract
Motivated by the recent detections of related alkoxy alcohols in the interstellar medium (ISM), we conducted a rotational spectroscopic study of 2-ethoxyethanol (C ₂ H ₅ OCH ₂ CH ₂ OH) to enable its search in the ISM. Quantum chemical calculations were performed to identify the lowest-energy conformers and predict their spectroscopic parameters. The rotational spectrum of the most stable conformer, −sc +sc ap ap-, was measured using complementary spectrometers covering the frequency regions 2–20, 6.5–18, 150–220, 230–330, and 370–500 GHz. A total of 2628 distinct transitions were assigned and fitted using a Watson A-reduced Hamiltonian, allowing the determination of rotational and centrifugal distortion constants up to the octic level. The resulting spectroscopic predictions are suitable for astronomical observations in the (sub)millimeter-wave domains. Using these new data, a search for −sc +sc ap ap- 2-ethoxyethanol was carried out toward NGC 6334I using Atacama Large Millimeter/submillimeter Array (ALMA) observations. No detection was obtained, and an upper limit column density of 1.1 × 10 ¹⁷ cm ⁻² was derived.
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BibTeX
@article{maillard2026extension,
title = {{Extension of 2-Ethoxyethanol Rotational Spectroscopy and Its Search in the Interstellar Medium}},
author = {Agathe Maillard and D. Archie Stewart and Laurent Margulès and Manuel Goubet and Roman A. Motiyenko and Elias M. Neeman and Brett A. McGuire},
journal = {The Astrophysical Journal},
year = {2026},
month = nov,
doi = {10.3847/1538-4357/aeaae5},
url = {https://iopscience.iop.org/article/10.3847/1538-4357/aeaae5},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Extension of 2-Ethoxyethanol Rotational Spectroscopy and Its Search in the Interstellar Medium
AU - Agathe Maillard
AU - D. Archie Stewart
AU - Laurent Margulès
AU - Manuel Goubet
AU - Roman A. Motiyenko
AU - Elias M. Neeman
AU - Brett A. McGuire
PY - 2026
DA - 2026/11/06
JO - The Astrophysical Journal
DO - 10.3847/1538-4357/aeaae5
UR - https://iopscience.iop.org/article/10.3847/1538-4357/aeaae5
AB - Motivated by the recent detections of related alkoxy alcohols in the interstellar medium (ISM), we conducted a rotational spectroscopic study of 2-ethoxyethanol (C ₂ H ₅ OCH ₂ CH ₂ OH) to enable its search in the ISM. Quantum chemical calculations were performed to identify the lowest-energy conformers and predict their spectroscopic parameters. The rotational spectrum of the most stable conformer, −sc +sc ap ap-, was measured using complementary spectrometers covering the frequency regions 2–20, 6.5–18, 150–220, 230–330, and 370–500 GHz. A total of 2628 distinct transitions were assigned and fitted using a Watson A-reduced Hamiltonian, allowing the determination of rotational and centrifugal distortion constants up to the octic level. The resulting spectroscopic predictions are suitable for astronomical observations in the (sub)millimeter-wave domains. Using these new data, a search for −sc +sc ap ap- 2-ethoxyethanol was carried out toward NGC 6334I using Atacama Large Millimeter/submillimeter Array (ALMA) observations. No detection was obtained, and an upper limit column density of 1.1 × 10 ¹⁷ cm ⁻² was derived.
SN - 1538-4357
SN - 0004-637X
ER -