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Title: Rotational Spectra in 29 Vibrationally Excited States of Interstellar Aminoacetonitrile

Abstract

We report a detailed spectroscopic investigation of the interstellar aminoacetonitrile, a possible precursor molecule of glycine. Using a combination of Stark and frequency-modulation microwave and millimeter wave spectroscopies, we observed and analyzed the room-temperature rotational spectra of 29 excited states with energies up to 1000 cm{sup −1}. We also observed the {sup 13}C isotopologues in the ground vibrational state in natural abundance (1.1%). The extensive data set of more than 2000 new rotational transitions will support further identifications of aminoacetonitrile in the interstellar medium.

Authors:
; ; ;  [1]
  1. Grupo de Espectroscopia Molecular (GEM), Edificio Quifima, Área de Química-Física, Laboratorios de Espectroscopia y Bioespectroscopia, Parque Científico UVa, Unidad Asociada CSIC, Universidad de Valladolid, E-47011 Valladolid (Spain)
Publication Date:
OSTI Identifier:
22661216
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal, Supplement Series; Journal Volume: 229; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACETONITRILE; AMINES; CARBON 13; CATALOGS; ELEMENT ABUNDANCE; FREQUENCY MODULATION; GLYCINE; INTERSTELLAR GRAINS; INTERSTELLAR SPACE; MICROWAVE RADIATION; MOLECULES; PRECURSOR; SPECTROSCOPY; VIBRATIONAL STATES

Citation Formats

Kolesniková, L., Alonso, E. R., Mata, S., and Alonso, J. L.. Rotational Spectra in 29 Vibrationally Excited States of Interstellar Aminoacetonitrile. United States: N. p., 2017. Web. doi:10.3847/1538-4365/AA5D13.
Kolesniková, L., Alonso, E. R., Mata, S., & Alonso, J. L.. Rotational Spectra in 29 Vibrationally Excited States of Interstellar Aminoacetonitrile. United States. doi:10.3847/1538-4365/AA5D13.
Kolesniková, L., Alonso, E. R., Mata, S., and Alonso, J. L.. Sat . "Rotational Spectra in 29 Vibrationally Excited States of Interstellar Aminoacetonitrile". United States. doi:10.3847/1538-4365/AA5D13.
@article{osti_22661216,
title = {Rotational Spectra in 29 Vibrationally Excited States of Interstellar Aminoacetonitrile},
author = {Kolesniková, L. and Alonso, E. R. and Mata, S. and Alonso, J. L.},
abstractNote = {We report a detailed spectroscopic investigation of the interstellar aminoacetonitrile, a possible precursor molecule of glycine. Using a combination of Stark and frequency-modulation microwave and millimeter wave spectroscopies, we observed and analyzed the room-temperature rotational spectra of 29 excited states with energies up to 1000 cm{sup −1}. We also observed the {sup 13}C isotopologues in the ground vibrational state in natural abundance (1.1%). The extensive data set of more than 2000 new rotational transitions will support further identifications of aminoacetonitrile in the interstellar medium.},
doi = {10.3847/1538-4365/AA5D13},
journal = {Astrophysical Journal, Supplement Series},
number = 2,
volume = 229,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
  • The millimeter-wave rotational spectra of SiC-13 and vibrationally excited SiC in the X3Pi state have been measured between 149 and 291 GHz in a laboratory discharge through SiH4 and CO. Hyperfine splittings in the SiC-13 spectra are well resolved, allowing accurate determination of all four hyperfine constants. The fine-structure, rotational, centrifugal distortion, and lambda-doubling constants for SiC-13 and v = 1 SiC have been determined to sufficient accuracy that the entire rotational spectrum can be calculated into the far-IR. 15 refs.
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  • Vibrationally excited HCN has been observed for the first time in the interstellar medium. The J = 3-2 rotational transitions of the l-doubled (0,1/sup 1d/,1c, 0) bending mode of HCN have been detected toward Orion-KL and IRC +10216. In Orion, the overall column density in the (0,1,0) mode, which exclusively samples the ''hot core,'' is 1.7-10/sup 16/ cm/sup -2/ and can be understood in terms of the ''doughnut'' model for Orion. The ground-state HCN column density implied by the excited-state observations is 2.3 x 10/sup 18/ cm/sup -2/ in the hot core, at least one order of magnitude greater thanmore » the column densities derived for HCN in its spike and plateau/doughnut components. Radiative excitation by 14 ..mu..m flux from IRc2 accounts for the (0,1,0) population provided the hot core is approx.6-7 x 10/sup 16/ cm distant from IRc2, in agreement with the ''cavity'' model for KL. Toward IRC +10216 we have detected J = 3-2 transitions of both (0,1/sup 1c/,/sup 1d/,0) and (0,2/sup 0/,0) excited states. The spectral profiles have been modeled to yield abundances and excitation conditions throughout the expanding envelope.« less