2026-10-11T11:55:07Z https://api.figshare.com/v2/oai

oai:figshare.com:article/33950719 2026-09-21T07:10:33Z category_1 category_4 category_915 category_7 category_19 category_873 category_45 category_64 category_69 portal_63 item_type_3 month_year_09_2026

A High-Resolution Rotational Analysis of 2‑Chloroethanol (HOCH₂CH₂Cl) and Its First Vibrationally Excited State Hayley A. Bunn (9765990) Holdson H. Liang (25081105) Brian J. Esselman (1333506) Paul L. Raston (1302183) Andi Pracko (25081108) Steven Shipman (25081111) Brant Billinghurst (8562126) Jianbao Zhao (1855051) Jes K. Jørgensen (7021847) Susanna L. Widicus Weaver (8989322) Biophysics Biochemistry Physical Sciences not elsewhere classified Medicine Pharmacology Chemical Sciences not elsewhere classified Sociology Cancer Inorganic Chemistry vibrational band origin simplest stable chlorohydrin reported upper limits report upper limits quadrupole coupling parameters provides spectral frequencies octic distortion constants 908 599 5 37 </ sup 35 </ sup wave spectrum reported well treated using resolution rotational spectrum 21 </ sub resolution rotational analysis 2 ‑ chloroethanol 2 </ sub interstellar chlorine chemistry fit </ sub r </ resolution infrared sup >< ></ sup wave spectra extensive analysis chlorine isotopologues interstellar medium thorough search squares fitting precise determination limited knowledge likely source ground state full set expected σ expected formation evade detection ethylene glycol either oxirane directly overlap chloroethanol continues astronomical data 060 mhz An extensive analysis of the high-resolution rotational spectrum (8–26 GHz, 140–700 GHz, 100–600 cm^–1) of the simplest stable chlorohydrin, 2-chloroethanol, is provided by combining high-resolution infrared, microwave, and millimeter-wave spectra. The ground state and first vibrationally excited state of both chlorine isotopologues (HOCH₂CH₂³⁵Cl and HOCH₂CH₂³⁷Cl) are well treated using a single-state distorted rotor Hamiltonian in the A reduction and I^<i>r</i> representation, reporting up to a full set of octic distortion constants. The extended microwave spectrum collected and the well-resolved quadrupole splitting observed therein allowed for the further refinement of quadrupole coupling parameters. Inclusion of rotationally resolved infrared transitions enabled the accurate and precise determination of the vibrational band origin of ν₂₁ for HOCH₂CH₂³⁵Cl (150.908 599 5 (43) cm^–1). The high spectral density made measurement and least-squares fitting of transitions in both rotational and high-resolution infrared spectra challenging and is the likely source of the larger-than-expected σ_fit value of up to 0.060 MHz for each fit. Nevertheless, the extended millimeter-wave spectrum reported here provides spectral frequencies that directly overlap with astronomical data, allowing for a more thorough search for this species in the interstellar medium. Despite its expected formation from HCl with either oxirane or ethylene glycol in the interstellar medium, 2-chloroethanol continues to evade detection. We report upper limits on the column density toward 30 astrophysically diverse regions. The reported upper limits do not provide significant new constraints on the chemistry of this species in the interstellar medium and highlight the limited knowledge of interstellar chlorine chemistry. 2026-09-21T00:00:00Z Dataset Dataset 10.1021/acsearthspacechem.6c00221.s002 https://figshare.com/articles/dataset/A_High-Resolution_Rotational_Analysis_of_2_Chloroethanol_HOCH_sub_2_sub_CH_sub_2_sub_Cl_and_Its_First_Vibrationally_Excited_State/33950719 CC BY-NC 4.0