J/A+A/629/A73 Rotational spectroscopy of methyl mercaptan (Zakharenko+, 2019)
Rotational spectroscopy of methyl mercaptan CH332SH at millimeter and
submillimeter wavelengths.
Zakharenko O., Ilyushin V.V., Lewen F., Mueller H.S.P., Schlemmer S.,
Alekseev E.A., Pogrebnyak M.L, Armieieva I.A., Dorovskaya O., Xu L.-H.,
Lees R.M.
<Astron. Astrophys. 629, A73 (2019)>
=2019A&A...629A..73Z 2019A&A...629A..73Z (SIMBAD/NED BibCode)
ADC_Keywords: Atomic physics
Keywords: methods: laboratory: molecular - techniques: spectroscopic -
ISM: molecules - astrochemistry - molecular data -
astronomical databases: miscellaneous
Abstract:
We present a new global study of the millimeter wave, submillimeter
wave, and THz spectra of the lowest three torsional states of methyl
mercaptan (CH3SH). New measurements have been carried out between 50
and 510GHz using the Kharkiv mm wave and the Cologne submm wave
spectrometers whereas THz spectra records were used from our previous
study. The new data involving torsion-rotation transitions with J up
to 61 and Ka up to 18 were combined with previously published
measurements and fitted using the rho-axis-method torsion-rotation
Hamiltonian. The final fit used 124 parameters to give an overall
weighted root- mean-square deviation of 0.72 for the dataset
consisting of 6965 microwave and 16345 FIR line frequencies sampling
transitions within and between the ground, first, and second excited
torsional states of the molecule. This investigation presents a
twofold expansion in the J quantum numbers and a significant
improvement in the fit quality, especially for the microwave part of
the data thus allowing us to provide improved predictions to support
astronomical observations.
Description:
ftfirdat.dat contains FTFIR data used in the current fit of methyl
mercaptan spectrum.
mwdata.dat contains microwave data used in the current fit of methyl
mercaptan spectrum.
predict.dat contains calculated spectrum of methyl mercaptan main
isotopolog for the ground, first, and second excited torsional states
in the range 1-2000GHz.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
ftfirdat.dat 68 19466 FTFIR data used in the current fit of
methyl mercaptan spectrum
mwdata.dat 75 7813 Microwave data used in the current fit of
methyl mercaptan spectrum
predict.dat 82 39296 Predicted transitions of the vt=0,1,2 torsional
states of methyl mercaptan in 1-2000GHz range
--------------------------------------------------------------------------------
Byte-by-byte Description of file: ftfirdat.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 A2 --- Sym1 Upper level symmetry species in G6
4- 5 I2 --- m1 Upper free rotor m quantum number
8- 9 I2 --- J1 Upper J quantum number
11- 13 I3 --- Ka1 Upper Ka quantum number
16- 17 I2 --- Kc1 Upper Kc quantum number
22- 23 A2 --- Sym0 Lower level symmetry species in G6
25- 26 I2 --- m0 Lower free rotor m quantum number
29- 30 I2 --- J0 Lower J quantum number
32- 34 I3 --- Ka0 Lower Ka quantum number
37- 38 I2 --- Kc0 Lower Kc quantum number
41- 49 F9.5 cm-1 Freq Measured transition frequency
52- 58 F7.5 cm-1 Unc Measurement uncertainty of transition frequency
61- 68 F8.5 cm-1 O-C Obs.-cal. difference in the fit
--------------------------------------------------------------------------------
Byte-by-byte Description of file: mwdata.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 A2 --- Sym1 Upper level symmetry species in G6
4- 5 I2 --- m1 Upper free rotor m quantum number
8- 9 I2 --- J1 Upper J quantum number
11- 13 I3 --- Ka1 Upper Ka quantum number
16- 17 I2 --- Kc1 Upper Kc quantum number
22- 23 A2 --- Sym0 Lower level symmetry species in G6
25- 26 I2 --- m0 Lower free rotor m quantum number
29- 30 I2 --- J0 Lower J quantum number
32- 34 I3 --- Ka0 Lower Ka quantum number
37- 38 I2 --- Kc0 Lower Kc quantum number
41- 51 F11.3 MHz Freq Measured transition frequency
53- 59 F7.3 MHz Unc Measurement uncertainty of transition frequency
62- 69 F8.3 MHz O-C Obs.-cal. difference in the fit
70- 75 A6 --- Com Source of the data (1)
--------------------------------------------------------------------------------
Note (1): Blank space - current work, letter coding from Xu et al.
(2012, J. Chem. Phys., 137, 104313):
Asterisks mark those lines which were excluded from the fit in
Xu et al. (Xu, L.-H., Lees, R. M., Crabbe, G. T., et al.,
2012, J. Chem. Phys., 137, 104313).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: predict.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 A2 --- Sym1 Upper level symmetry species in G6
4- 5 I2 --- m1 Upper free rotor m quantum number
8- 9 I2 --- J1 Upper J quantum number
11- 13 I3 --- Ka1 Upper Ka quantum number
16- 17 I2 --- Kc1 Upper Kc quantum number
22- 23 A2 --- Sym0 Lower level symmetry species in G6
25- 26 I2 --- m0 Lower free rotor m quantum number
29- 30 I2 --- J0 Lower J quantum number
32- 34 I3 --- Ka0 Lower Ka quantum number
37- 38 I2 --- Kc0 Lower Kc quantum number
40- 52 F13.4 MHz Freq Predicted transition frequency
54- 60 F7.4 MHz Unc Predicted uncertainty of transition frequency
64- 72 F9.4 cm-1 Elow The energy of the lower state
76- 82 F7.3 D+2 mu2S Linestrength multiplied by dipole moment squared
--------------------------------------------------------------------------------
Acknowledgements:
Holger S.P. Muller, hspm(at)ph1.uni-koeln.de
(End) Holger S.P. Muller [Univ. Cologne], Patricia Vannier [CDS] 31-Jul-2019