skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Millimeter-wave and Submillimeter-wave Spectra of Aminoacetonitrile in the Three Lowest Vibrational Excited States

Abstract

It is important to study possible precursors of amino acids such as glycine to enable future searches in interstellar space. Aminoacetonitrile (NH{sub 2}CH{sub 2}CN) is one of the most feasible molecules for this purpose. This molecule was already detected toward Sgr B2(N). Aminoacetonitrile has a few low-lying vibrational excited states, and transitions within these states may be found in space. In this study, the pure-rotational transitions in the three lowest vibrational states in the 80–450 GHz range have been assigned and analyzed. It was found to be very important to include Coriolis coupling between the two lowest vibrational fundamentals, while the third one was unperturbed. The partition function was evaluated considering these new results.

Authors:
; ;  [1];  [2]; ;  [3]
  1. Dipartimento di Chimica “Giacomo Ciamician”, Università di Bologna, via Selmi 2, I-40126 Bologna (Italy)
  2. Department of Physics, Faculty of Science, University of Toyama, 3190 Gofuku, Toyama 930-8555 (Japan)
  3. Department of Environmental Science, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, 274-8510 (Japan)
Publication Date:
OSTI Identifier:
22661115
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal, Supplement Series; Journal Volume: 230; 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; ACETONITRILE; AMINES; COUPLING; GHZ RANGE; GLYCINE; INTERSTELLAR SPACE; MOLECULES; PARTITION FUNCTIONS; VIBRATIONAL STATES

Citation Formats

Esposti, Claudio Degli, Dore, Luca, Melosso, Mattia, Kobayashi, Kaori, Fujita, Chiho, and Ozeki, Hiroyuki, E-mail: ozeki@env.sci.toho-u.ac.jp. Millimeter-wave and Submillimeter-wave Spectra of Aminoacetonitrile in the Three Lowest Vibrational Excited States. United States: N. p., 2017. Web. doi:10.3847/1538-4365/AA7335.
Esposti, Claudio Degli, Dore, Luca, Melosso, Mattia, Kobayashi, Kaori, Fujita, Chiho, & Ozeki, Hiroyuki, E-mail: ozeki@env.sci.toho-u.ac.jp. Millimeter-wave and Submillimeter-wave Spectra of Aminoacetonitrile in the Three Lowest Vibrational Excited States. United States. doi:10.3847/1538-4365/AA7335.
Esposti, Claudio Degli, Dore, Luca, Melosso, Mattia, Kobayashi, Kaori, Fujita, Chiho, and Ozeki, Hiroyuki, E-mail: ozeki@env.sci.toho-u.ac.jp. Thu . "Millimeter-wave and Submillimeter-wave Spectra of Aminoacetonitrile in the Three Lowest Vibrational Excited States". United States. doi:10.3847/1538-4365/AA7335.
@article{osti_22661115,
title = {Millimeter-wave and Submillimeter-wave Spectra of Aminoacetonitrile in the Three Lowest Vibrational Excited States},
author = {Esposti, Claudio Degli and Dore, Luca and Melosso, Mattia and Kobayashi, Kaori and Fujita, Chiho and Ozeki, Hiroyuki, E-mail: ozeki@env.sci.toho-u.ac.jp},
abstractNote = {It is important to study possible precursors of amino acids such as glycine to enable future searches in interstellar space. Aminoacetonitrile (NH{sub 2}CH{sub 2}CN) is one of the most feasible molecules for this purpose. This molecule was already detected toward Sgr B2(N). Aminoacetonitrile has a few low-lying vibrational excited states, and transitions within these states may be found in space. In this study, the pure-rotational transitions in the three lowest vibrational states in the 80–450 GHz range have been assigned and analyzed. It was found to be very important to include Coriolis coupling between the two lowest vibrational fundamentals, while the third one was unperturbed. The partition function was evaluated considering these new results.},
doi = {10.3847/1538-4365/AA7335},
journal = {Astrophysical Journal, Supplement Series},
number = 2,
volume = 230,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}
  • The rotational-torsional spectrum of (C-13)H/sub 3/OH is presented in both the symmetric and degenerate substates of the first two excited torsional states. Of the new transitions reported, 122 lines are from the v(t) = 1 torsional state and 110 lines are from the v(t) = 2 torsional state, and all are confined to the rotational quantum number J = 8 or less. The data are combined with previously reported millimeter and submillimeter data for the v(t) = 0 torsional state and 44 previously measured excited torsional state lines to form a global data set of 596 transitions, which is analyzedmore » and fitted using an extended internal axis method. The fit results in an overall rms deviation of 1.98 MHz. The spectral constants generated by the fit are used to predict an additional 123 lines of (C-13)H/sub 3/OH in the v(t) = 1,2 excited torsional states with frequencies up to 612 GHz and rotational quantum number J = 11 or less. 24 references.« less
  • A compilation of the available spectroscopic millimeter- and submillimeter-wave data of the ground and first excited states of {sup 13}C{sub 1}-methyl formate (H{sup 13}COOCH{sub 3}) has been carried out. The exhaustive analysis of the available transition lines of H{sup 13}COOCH{sub 3} has led to the assignment of 7457 spectral lines by means of a global fit of 45 parameters, using the Rho-Axis Method and the BELGI-Cs code, with a resulting unitless standard deviation of 0.57. Over 1600 lines are included for the first time in the fit. In addition, the line strengths of spectral lines are also calculated using themore » most recent experimental measurement of the electric dipole moment. In conclusion, the present study represents a notable improvement with respect to previous H{sup 13}COOCH{sub 3} spectral analyses. Therefore, the better accuracy of the present analysis may help the future identification of new H{sup 13}COOCH{sub 3} lines in the interstellar and circumstellar media, and may contribute to decrease some of the spectral confusion due to these species in astronomical surveys.« less
  • Precision frequency measurements have been made on the J = 0 yields 1 transitions of the deuterium halides DCl, DBr. and DI. The molecular constants derived from these measurements are tabulated. (auth)
  • Highly resolved emission, excitation, and resonantly line-narrowed spectra, as well as emission decay properties of [Rh(bpy-h{sub 8}){sub n}(bpy-d{sub 8}){sub 3-n}]{sup 3+} (n=0, 2, 3; bpy = 2,2{prime}-bipyridine)dopes into [Zn(bpy-h{sub 8}){sub 3}] (ClO{sub 4}){sub 2} are presented for the first time. [Rh(bpy-h{sub 8}){sub 3}]{sup 3+} exhibit one low-lying triplet T{sub 1} at 22,757 {+-} 1 and 22,818 {+-} 1 cm{sup -1}, respectively (blue shift 61 cm{sup -1}), while [Rh(bpy-h{sub 8}){sub 2}(bpy-d{sub 8})]{sup 3+} has two low-lying triplets at 22 757 {+-} 1 and 22 818 {+-} 1 cm{sup -1}.
  • We describe measurements of the complete angular dependence of the optically detected magnetic resonance (ODMR) spectra of the lowest triplet states of benzophenone, carbonyl-/sup 13/C-benzophenone, 4,4'-difluorobenzophenone, 4,4'-dichlorobenzophenone, and 4,4'-dibromobenzophenone in 4,4'-dibromodiphenylether host crystals at liquid helium temperatures. The principal axes and values of D (including the absolute signs) and g are reported and used to evaluate the spin--spin and spin--orbit contributions to the fine-structure tensor of the parent molecule. It is found that the dipolar contributions to D in /sup 3/(n,..pi..*) benzophenone are at least a factor of 2 less than recent ab initio estimates of the spin--spin contributions tomore » D in /sup 3/A/sub 2/ formaldehyde. Carbon-13 hyperdfine splittings have been observed in the ODMR spectra of /sup 13/C-benzophenone; an analysis of these yields estimates of the orbital spin densities rho/sub 2//sub s//sup() CO/approx. =0.008 and rho/sub 2//sub p/x-italic/sup() CO/< or =0.14 and suggests that the C/sub 1/--C(O) --C/sub 1/' fragment is planar. The fine-structure parameters of triplet benzophenone are strongly influenced by halogen atoms in the para ring positions. The ODMR spectra of the 4,4'-difluoro and 4,4'-dibromo derivatives also exhibit ring halogen atom hyperfine structure from which the estimate rho/sub 2//sub p/..pi../sup C/4> or =0.10 is obtained. Taken together, the results of this investigation suggest that as much as 50% of the total spin density in the lowest triplet state of benzophenone itself resides on the aromatic rings, thereby accounting for the reduction in the dipolar contributions to D in the parent molecule and for the changes in the principal values (and directions) of D which occur in its heavy-atom substituted derivatives.« less