Rotational spectra of isotopic species of methyl cyanide, CH${}_3$CN, in their $v_8=1$ excited vibrational states

Abstract

Methyl cyanide is an important trace molecule in space, especially in star-forming regions where it is one of the more common molecules used to derive kinetic temperatures. We want to obtain accurate spectroscopic parameters of minor isotopologs of methyl cyanide in their lowest excited $v_8=1$ vibrational states to support astronomical observations, in particular, with interferometers such as ALMA. The laboratory rotational spectrum of methyl cyanide in natural isotopic composition has been recorded from the millimeter to the terahertz regions. Transitions with good signal-to-noise ratios could be identified for the three isotopic species CH${}_3^{13}$CN, ${}^{13}$CH${}_3$CN, and CH${}_3$C(15)N up to about 1.2 THz ($J^{\prime \prime }\le 66$). Accurate spectroscopic parameters were obtained for all three species. The present data were already instrumental in identifying $v_8=1$ lines of methyl cyanide with one ${}^{13}$C in IRAM 30 m and ALMA data toward Sagittarius B2(N).

arXiv comment6 pages, 1 figure, article appeared; CDMS links and two references updated

References in corpus (15)

• Complex organic molecules in the interstellar medium: IRAM 30 m line survey of Sagittarius B2(N) and (M)
• Detection of the simplest sugar, glycolaldehyde, in a solar-type protostar with ALMA
• Increased complexity in interstellar chemistry: Detection and chemical modeling of ethyl formate and n-propyl cyanide in Sgr B2(N)
• Detection of a branched alkyl molecule in the interstellar medium: iso-propyl cyanide
• Exploring Molecular Complexity with ALMA (EMoCA): Deuterated complex organic molecules in Sagittarius B2(N2)
• Exploring molecular complexity with ALMA (EMoCA): Alkanethiols and alkanols in Sagittarius B2(N2)
• The first ALMA view of IRAS 16293-2422: Direct detection of infall onto source B and high-resolution kinematics of source A
• First results from the CALYPSO IRAM-PdBI survey. II. Resolving the hot corino in the Class 0 protostar NGC 1333-IRAS2A
• Rotational spectroscopy of isotopic vinyl cyanide, H${}_2$C=CH$-$C$\equiv$N, in the laboratory and in space
• Rotational spectra of isotopic species of methyl cyanide, CH${}_3$CN, in their ground vibrational states up to terahertz frequencies
• Searching for Trans Ethyl Methyl Ether in Orion KL
• Rotational spectroscopy as a tool to investigate interactions between vibrational polyads in symmetric top molecules: low-lying states $v_8\le 2$ of methyl cyanide, CH${}_3$CN
• Physical conditions in the Protoplanetary Nebula CRL 618 derived from observations of vibrationally excited HCCCN
• Laboratory spectroscopy of 1,2-propanediol at millimeter and submillimeter wavelengths
• Millimeter Wave and Terahertz Spectra and Global Fit of Torsion-Rotation Transitions in the Ground, First and Second Excited Torsional States of 13CH3OH Methanol

Cited by in corpus (9)

• Exploring Molecular Complexity with ALMA (EMoCA): Deuterated complex organic molecules in Sagittarius B2(N2)
• Submillimeter spectroscopy of H${}_2$C${}^{17}$O and a revisit of the rotational spectra of H${}_2$C${}^{18}$O and H${}_2$C${}^{16}$O
• Laboratory spectroscopic study of isotopic thioformaldehyde, H${}_2$CS, and determination of its equilibrium structure
• Vibrational Satellites of C${}_2$S, C${}_3$S, and C${}_4$S: Microwave Spectral Taxonomy as a Stepping Stone to the Millimeter-Wave Band
• Laboratory spectroscopic study and astronomical detection of vibrationally excited n-propyl cyanide
• Toward a global model of the interactions in low-lying states of methyl cyanide: rotational and rovibrational spectroscopy of the $v_4=1$ state and tentative interstellar detection of the $v_4=v_8=1$ state in Sgr B2(N)
• Reexploring Molecular Complexity with ALMA: Insights into chemical differentiation from the molecular composition of hot cores in Sgr B2(N2)
• Rotational spectroscopy of singly ${}^{13}$C substituted isotopomers of propyne and determination of a semi-empirical equilibrium structure
• Rotational Spectroscopy as a Tool to Study Vibration-Rotation Interaction: Investigations of ${}^{13}$CH${}_3$CN and CH${}_3$${}^{13}$CN up to $v_8=2$ and a Search for $v_8=2$ Transitions toward Sagittarius B2(N)