J/A+A/589/A127 Dimethyl sulfide laboratory um, mm & FIR spectra (Jabri+, 2016)
Laboratory microwave, millimeter wave and far-infrared spectra of dimethyl
sulfide
Jabri A., Nguyen H.V.L., Mouhib H., Tchana F.K., Manceron L., Stahl W.,
Kleiner I.
<Astron. Astrophys. 589, A127 (2016)>
=2016A&A...589A.127J 2016A&A...589A.127J (SIMBAD/NED BibCode)
ADC_Keywords: Atomic physics
Keywords: astrochemistry - line: identification - ISM: molecules
Abstract:
Dimethyl sulfide, CH3SCH3 (DMS), is a nonrigid, sulfur-containing
molecule whose astronomical detection is considered to be possible in
the interstellar medium. Very accurate spectroscopic constants were
obtained by a laboratory analysis of rotational microwave and
millimeter wave spectra, as well as rotation-torsional far-infrared
(FIR) spectra, which can be used to predict transition frequencies for
a detection in interstellar sources.
This work aims at the experimental study and theoretical analysis of
the ground torsional state and ground torsional band ν15 of DMS
in a large spectral range for astrophysical use.
Description:
DMS was purchased from Alfa Aesar GmbH & Co KG, Karlsruhe, Germany and
used without further purification.
The microwave spectrum was measured in the frequency range 2-40GHz
using two Molecular Beam Fourier Transform MicroWave (MB-FTMW)
spectrometers in Aachen, Germany. The millimeter spectrum was recorded
in the 50-110GHz range. The FIR spectrum was measured for the first
time at high resolution using the FT spectrometer and the newly built
cryogenic cell at the French synchrotron SOLEIL.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
appenb.dat 92 602 *Microwave and millimeter-wave range
appenc.dat 72 578 *Far-infrared range
appene.dat 94 7158 A line-list of all rotational transitions
reliably predicted between 0 and 300GHz with
the set of spectroscopic parameters
determined in Appendix A
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Note on appenb.dat: Assignments, observed frequencies, calculated frequencies
from the BELGI-Cs-2tops fit, residuals, line strengths, lower and upper state
energy levels for dimethyl sulfide CH3SCH3 transitions from v11=0,v15=0
(ground state) v11=1,v15=0 and v11=0,v15=1 (first excited torsional state)
included in the fit with parameters of Appendice A.
Note on appenc.dat: Assignments, observed frequencies, calculated frequencies
from the BELGI-Cs-2Tops fit, residuals, lower and upper state energy levels
for dimethyl sulfide CH3SCH3 transitions in the torsional band
v15=1⟵v15=0 included in the fit with parameters of Appendix A.
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Byte-by-byte Description of file: appenb.dat
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Bytes Format Units Label Explanations
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1 I1 --- v111 [0/1] Observed v11 upper state (G1)
2 I1 --- v151 [0/1] Observed v15 upper state (G1)
4- 5 I2 --- J1 Observed J upper state
7- 8 I2 --- Ka1 Observed Ka upper state
10- 11 I2 --- Kc1 Observed Kc upper state
13 I1 --- v110 [0/1] Observed v11 lower state (G1)
14 I1 --- v150 [0/1] Observed v15 lower state (G1)
16- 17 I2 --- J0 Observed J lower state
19- 20 I2 --- Ka0 Observed Ka lower state
22- 23 I2 --- Kc0 Observed Kc lower state
25- 34 F10.3 MHz Freq.Obs Observed line frequency
36- 38 I3 kHz e_Freq.Obs rms uncertainty on Freq.Obs (G2)
40- 49 F10.3 MHz Freq.Cal Calculated line frequency
51- 55 F5.3 MHz e_Freq.Cal ? rms uncertainty on Freq.Cal
57- 62 F6.3 MHz O-C Difference between the experimental and
calculated frequencies
64- 71 F8.5 D+2 S*mu**2 Calculated line strength (3)
73- 80 F8.4 cm-1 E0 Upper state energy including the
zero-point torsional energy
82- 89 F8.4 cm-1 E1 Lower state energy including the
zero-point torsional energy
91- 92 A2 --- Sym Symmetry species in the
C-3v X c+3v direct product (4)
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Note (3): Note that the line strengths are given as S*mu**2. To obtain
intensities the line strengths need to be multiplied by appropriate
statistical weights, Boltzmann factor and divided by the total partition
function (see appendix C).
Note (4): The spin-weight statistics for the transitions AA: EE: AE: EA depend
on the parity of KaKc, i.e. 6:16:4:2 for KaKc: ee-oo and
10:16:4:6 for KaKc: eo-oe (Vacherand et al. 1987).
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Byte-by-byte Description of file: appenc.dat
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Bytes Format Units Label Explanations
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1 I1 --- v111 [0] Observed v11 upper state
2 I1 --- v151 [1] Observed v15 upper state
4- 5 I2 --- J1 J upper state
7- 8 I2 --- Ka1 Ka upper state
10- 11 I2 --- Kc1 Kc upper state
13 I1 --- v110 [0] v11 lower state
14 I1 --- v150 [0] v15 lower state
16- 17 I2 --- J0 J lower state
19- 20 I2 --- Ka0 Ka lower state
22- 23 I2 --- Kc0 Kc lower state
25- 32 F8.4 MHz Freq.Obs Observed line frequency
34 I1 kHz e_Freq.Obs rms uncertainty on Freq.Obs
36- 43 F8.4 MHz Freq.Cal Calculated line frequency
45- 51 F7.4 MHz O-C Difference between the experimental and
calculated frequencies
53- 60 F8.4 cm-1 E0 Upper state energy including the zero-point
torsional energy calculated at 187.6294cm-1
62- 69 F8.4 cm-1 E1 Lower state energy including the zero-point
torsional energy calculated at 187.6294cm-1
71- 72 A2 --- Sym Symmetry species in the
C-3v X c+3v direct product
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Byte-by-byte Description of file: appene.dat
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Bytes Format Units Label Explanations
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1 I1 --- v111 [0] Observed v11 upper state (G1)
2 I1 --- v151 [0] Observed v15 upper state (G1)
4- 5 I2 --- J1 Observed J upper state
7- 9 I3 --- Ka1 Observed Ka upper state
11- 12 I2 --- Kc1 Observed Kc upper state
14 I1 --- v110 [0] Observed v11 lower state (G1)
15 I1 --- v150 [0] Observed v15 lower state (G1)
17- 18 I2 --- J0 Observed J lower state
20- 22 I3 --- Ka0 Observed Ka lower state
24- 25 I2 --- Kc0 Observed Kc lower state
27- 36 F10.3 MHz Freq.Obs ? Observed line frequency
38- 40 I3 kHz e_Freq.Obs ? rms uncertainty on Freq.Obs (G2)
42- 51 F10.3 MHz Freq.Cal Calculated line frequency
53- 57 F5.3 MHz e_Freq.Cal rms uncertainty on Freq.Cal
59- 64 F6.3 MHz O-C ? Difference between the experimental and
calculated frequencies
66- 73 F8.5 D+2 Smu+2 Calculated line strength
75- 82 F8.4 cm-1 E0 Upper state energy including the
zero-point torsional energy
84- 91 F8.4 cm-1 E1 Lower state energy including the
zero-point torsional energy
93- 94 A2 --- Sym Symmetry species in the
C-3v X c+3v direct product
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Global notes:
Note (G1): Energy levels of the EA, AE and EE species have a signed Ka value
(Herbst et al. 1984).
Note (G2): Estimated experimental uncertainty are given according to the source
of data. 5kHz: MB-FTMW Aachen; 40kHz: millimeter-wave Aachen; 100kHz:
(Vacherand et al. 1987); 50kHz: millimeter-wave (Niide & Hayashi 2004).
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Acknowledgements:
Atef Jabri, Atef.jabri(at)lisa.u-pec.fr
(End) Patricia Vannier [CDS] 25-Feb-2016