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Isofulminic acid, HONC: Ab initio theory and microwave spectroscopy
Mirjana Mladenović1, Marius Lewerenz, Michael C McCarthy
1Laboratoire Modélisation et Simulation Multi Echelle, MSME FRE3160 CNRS, Université Paris-Est, 5 bd Descartes, 77454 Marne la Vallée, Cedex 2, France. mladenov@univ-mlv.fr
The Journal of Chemical Physics
|November 10, 2009
Summary
Isofulminic acid (HONC), an energetic isomer of isocyanic acid, has been spectroscopically detected. Its high polarity and presence of isomers in space make it a candidate for radio telescope detection.
Area of Science:
- * Astrochemistry
- * Molecular Spectroscopy
- * Theoretical Chemistry
Background:
- * Isofulminic acid (HONC) is the most energetic stable isomer of isocyanic acid (HNCO).
- * Previous studies have focused on the isomers HNCO, HOCN, and HCNO, which have been detected in space.
- * The spectroscopic properties and astronomical potential of HONC remained largely unexplored.
Purpose of the Study:
- * To spectroscopically detect and characterize isofulminic acid (HONC).
- * To provide high-level theoretical calculations for electronic and spectroscopic parameters of HONC.
- * To assess the potential for astronomical detection of HONC.
Main Methods:
- * Rotational spectroscopy (Fourier transform microwave spectroscopy) in a molecular beam.
- * Coupled cluster electronic structure calculations.
- * Ab initio calculations for predicting spectroscopic constants.
Main Results:
- * Fundamental rotational transitions of four isotopic species of HONC were detected.
- * Rotational constants and quadrupole coupling constants were derived and agreed well with theoretical predictions.
- * High-level ab initio calculations provided dipole moment, vibrational frequencies, and other spectroscopic parameters.
Conclusions:
- * The spectroscopic detection and characterization of isofulminic acid (HONC) were successful.
- * Isofulminic acid is a polar molecule with properties suitable for radio telescope detection.
- * Further astronomical observations are warranted to search for HONC in interstellar space.
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