The rotational spectrum of ¹³C₂HD in the ground and excited bending states

Abstract

The pure rotational spectrum of ¹³C₂HD was recorded in the range 100–700 GHz. Lines belonging to the ground vibrational state were observed from J^″ = 1 to J^″ = 11. Several absorption lines were also detected in the bending states v₄ = 1 (Π), v₅ = 1 (Π), v₄ = 2 (Σ⁺ and Δ), v₅ = 2 (Σ⁺ and Δ), v₄ = v₅ = 1 (Σ⁻, Σ⁺ and Δ), v₄ = 3 (Π and Φ) and v₅ = 3 (Π and Φ). The transition frequencies measured in this work were fitted together with all the infrared lines available in the literature. The global fit allowed a very accurate determination of the vibrational, rotational and ℓ-type interaction parameters for the bending states of this molecule.

Keywords:

• infrared spectroscopy
• rotational spectroscopy
• ¹³C₂HD
• global fit
• ground and excited bending states

Acknowledgements

The authors acknowledge the Università di Bologna and the Ministero della Ricerca e dell’Università for financial support under the grant PRIN09 High-resolution Spectroscopy for Atmospherical and Astrochemical Research: Experiment, Theory and Applications’. The authors also thank Prof. G. Di Lonardo for helping the analysis of the spectra.

Notes

^a obs–calc. values from the global analysis are in parentheses. Lines marked with an asterisk are overlapped with other lines.

^be and f components not resolved. See text for details about the fit.

^a Estimated uncertainties (1σ) are given in parentheses in units of the last figure quoted.

^b Fixed in the analysis.

^a Estimated uncertainties (1σ) are given in parentheses in units of the last figure quoted.

^b Fixed in the analysis.

^a Estimated uncertainties (1σ) are given in parentheses in units of the last figure quoted.

^a Extrapolated from v₅ = 2 state.