Show pageOld revisionsBacklinksBack to top This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong. ===== Detection of Ethyl Cyanide in the ISM ===== Ethyl cyanide, C<sub>2</sub>H<sub>5</sub>CN, aka propanenitrile, is a fairly prototypical hot core molecule. It was detected first toward OMC-1 and Sgr B2:\\ D. R. Johnson, F. J. Lovas, C. A. Gottlieb, E. W. Gottlieb, M. M. Litvak, P. Thaddeus, and M. Guélin,\\ **[[https://ui.adsabs.harvard.edu/abs/1977ApJ...218..370J|Detection of Interstellar Ethyl Cyanide]]**\\ //Astrophys. J.// **218**, L370–L376 (1977).\\ \\ More recently, however, it has also been detected toward a low-mass star-forming region:\\ S. Cazaux, A. G. G. M. Tielens, C. Ceccarelli, A. Castets, V. Wakelam, E. Caux, B. Parise, D. Teyssier,\\ **[[https://doi.org/10.1086/378038|The Hot Core around the Low-mass Protostar IRAS 16293-2422: Scoundrels Rule!]]**\\ //Astrophys. J.// **593**, L51–L55 (2003).\\ \\ Ethyl cyanide in its two lowest vibrational states //v//<sub>13</sub> ≡ //v//<sub>b</sub> = 1 (in plane CCN bend; ca. 206.5 cm<sup>–1</sup>) and //v//<sub>21</sub> ≡ //v//<sub>t</sub> = 1 (torsion; ca. 212.7 cm<sup>–1</sup>) has been detected in a 3, 2, and 1 mm line survey carried out with SEST:\\ E. Gibb, A. Nummelin, W. M. Irvine, D. C. B. Whittet, and P. Bergman,\\ **[[https://doi.org/10.1086/317805|Chemistry of the Organic-Rich Hot Core G327.3–0.6]]**\\ //Astrophys. J.// **545**, 309–326 (2000).\\ This account apparently did not receive the appropriate attention. Later, observations toward Sgr B2(N-LMH) were reported:\\ D. M. Mehringer, J. C. Pearson, J. Keene, and T. G. Philips,\\ **[[https://doi.org/10.1086/386357|Detection of Vibrationally Excited Ethyl Cyanide in the Interstellar Medium]]**\\ //Astrophys. J.// **608**, 306–313 (2004).\\ \\ These states as well as higher vibrational states up to v<sub>12</sub> = 1 at 770 K were detected toward Orion KL by\\ A. M. Daly, C. Bermúdez, A. López, B. Tercero, J. C. Pearson, N. Marcelino, J. L. Alonso, and J. Cernicharo,\\ **[[https://doi.org/10.1088/0004-637X/768/1/81|Laboratory Characterization and Astrophysical Detection of Vibrationally Excited States of Ethyl Cyanide]]**\\ //Astrophys. J.// **768**, Art. No. 81 (2013).\\ They were also detected in Sagittarius B2(N) by\\ A. Belloche, H. S. P. Müller, K. M. Menten, P. Schilke, and C. Comito:\\ **[[https://doi.org/10.1051/0004-6361/201321096|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]**\\ //Astron. Astrophys.// **559**, Art. No. A47 (2013).\\ \\ The three <sup>13</sup>C isotopic species have been reported first in observations toward Orion IRc2 by\\ K. Demyk, H. Mäder, B. Tercero, J. Cernicharo, J. Demaison, L. Margulès, M. Wegner, S. Keipert, and M. Sheng,\\ **[[https://doi.org/10.1051/0004-6361:20066955|Isotopic Ethyl Cyanide <sup>13</sup>CH<sub>3</sub>CH<sub>2</sub>CN, CH<sub>3</sub><sup>13</sup>CH<sub>2</sub>CN, and CH<sub>3</sub>CH<sub>2</sub><sup>13</sup>CN:\\ Laboratory Rotational Spectrum and Detection in Orion]]**\\ //Astron. Astrophys.// **466**, 255–259 (2007).\\ They were also detected in Sagittarius B2(N) by\\ H. S. P. Müller, A. Belloche, K. M. Menten, C. Comito, and P. Schilke,\\ **[[https://doi.org/10.1016/j.jms.2008.03.016|Rotational Spectroscopy of Isotopic Vinyl Cyanide, H<sub>2</sub>C=CH–C≡N, in the Laboratory and in Space]]**,\\ //J. Mol. Spectrosc.// **250**, 319–325 (2008).\\ \\ The detection of the <sup>15</sup>N isotopolog (in Orion KL) was reported first by\\ L. Margulès, R. Motiyenko, K. Demyk, B. Tercero, J. Cernicharo, M. Sheng, M. Weidmann, J. Gripp, H. Mäder, and J. Demaison,\\ **[[https://doi.org/10.1051/0004-6361:200810889|Rotational Spectrum of Deuterated and <sup>15</sup>N Ethyl Cyanides: CH<sub>3</sub>CHDCN and CH<sub>2</sub>DCH<sub>2</sub>CN and of CH<sub>3</sub>CH<sub>2</sub>C<sup>15</sup>N]]**\\ //Astron. Astrophys.// **493**, 565 (2009).\\ The isotopolog was also detected in Sagittarius B2(N2), the northern, secondary hot-core of Sgr B2(N), by\\ A. Belloche, H. S. P. Müller, R. T. Garrod, and K. M. Menten,\\ **[[https://doi.org/10.1051/0004-6361/201527268|Exploring Molecular Complexity with ALMA (EMoCA): Deuterated Complex Organic Molecules in Sagittarius B2(N2)]]**\\ //Astron. Astrophys.// **587**, Art. No. A91 (2016).\\ \\ A. Belloche, H. S. P. Müller, R. T. Garrod, and K. M. Menten\\ were\\ **[[https://doi.org/10.1051/0004-6361/201527268|Exploring Molecular Complexity with ALMA (EMoCA): Deuterated Complex Organic Molecules in Sagittarius B2(N2)]]**\\ //Astron. Astrophys.// **587**, Art. No. A91 (2016).\\ They report the tentative detection of deuterated ethyl cyanide in the course of their 3 mm line survey with ALMA. Their ratios of the normal species to the one deuterated at the out-of-plane methyl group position and at the methylene group are about 2000, the upper limit to the one deuterate at the in-plane methyl group position is 4000, consistent with the other positions which occur twice each. The number of clean lines was so small that the authors refrained from claiming a firm detection.\\ \\ L. Margulès, A. Belloche, H. S. P. Müller, R. A. Motiyenko, J.-C. Guillemin, R. T. Garrod, and K. M. Menten,\\ reported on the\\ **[[https://doi.org/10.1051/0004-6361/201628309|Spectroscopic Study and Astronomical Detection of Doubly <sup>13</sup>C-Substituted Ethyl Cyanide]]**\\ //Astron. Astrophys.// **590**, Art. No. A93 (2016).\\ The astronomical detection was made in Sagittarius B2(N2) in the course of their 3 mm line survey with ALMA.\\ \\ ---- Contributor(s): H. S. P. Müller; 07, 2004; 03/04 2007; 10, 2010; 06, 2016 ---- molecules/ism/etcn.txt Last modified: 2026/08/25 10:38by mueller