Comprehensive rotational study and astronomical search for cyclopropanecarboxaldehyde.
C Cabezas1, E M Neeman2, B Tercero3,4
1Instituto de Física Fundamental (IFF-CSIC). Group of Molecular Astrophysics, C/Serrano 123, 28006 Madrid, Spain.
Astronomy and Astrophysics
|April 9, 2021
Summary
Accurate rotational parameters for cyclopropanecarboxaldehyde were determined, aiding its detection in interstellar space. This study provides crucial data for identifying this formyl group-containing molecule in cosmic clouds.
Area of Science:
- * Astrochemistry
- * Molecular Spectroscopy
Background:
- * Numerous formyl group (HCO) molecules exist in the interstellar medium (ISM).
- * High-resolution spectroscopic data for simple formyl species are scarce, hindering astrophysical detection.
- * Cyclopropanecarboxaldehyde is a candidate molecule for ISM detection but lacks precise rotational parameters.
Purpose of the Study:
- * To obtain precise rotational parameters for cyclopropanecarboxaldehyde (c-C3H5CHO) for astrophysical detection.
- * To identify and characterize vibrational excited states of both cis and trans isomers.
- * To search for cyclopropanecarboxaldehyde in interstellar molecular clouds.
Main Methods:
- * Measured the rotational spectrum of cyclopropanecarboxaldehyde using the GACELA broadband high-resolution rotational spectrometer (31.5-50 GHz and 72-116.5 GHz).
- * Employed high-level theoretical calculations to support spectral analysis and identify vibrational excited states.
- * Utilized spectral surveys from ALMA and IRAM 30 m telescopes for astrophysical searches.
Main Results:
- * Determined accurate rotational parameters for the ground states of both cis and trans cyclopropanecarboxaldehyde isomers, enabling predictions up to 300 GHz.
- * Identified 12 and 6 vibrationally excited states for the trans and cis isomers, respectively.
- * Found the trans isomer concentration to be ~1.2 times higher than the cis isomer in gas phase.
- * Detected cyclopropanecarboxaldehyde in Orion KL and Sgr B2(N) molecular clouds.
Conclusions:
- * Precise rotational parameters and identified excited states facilitate the astrophysical detection of cyclopropanecarboxaldehyde.
- * The trans isomer is more abundant than the cis isomer in the gas phase.
- * This study provides essential spectroscopic data for identifying new molecules in the interstellar medium.
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