J/ApJS/166/650 mm/sbmm spectrum of iso-propanol (Maeda+, 2006)
The millimeter- and submillimeter-wave spectrum of iso-propanol
[(CH3)2CHOH].
Maeda A., Medvedev I.R., De Lucia F.C., Herbst E.
<Astrophys. J. Suppl. Ser., 166, 650-658 (2006)>
=2006ApJS..166..650M 2006ApJS..166..650M
ADC_Keywords: Atomic physics
Keywords: catalogs - molecular data - submillimeter - techniques: spectroscopic
Abstract:
Iso-propanol [(CH3)2CHOH], an isomer of n-propanol, has been
studied in the millimeter- and submillimeter-wave region of the
electromagnetic spectrum with our FASSST spectrometer through 360GHz.
Spectra arising from the ground vibrational state of all three
hydroxyl torsional substates, given the labels symmetric gauche,
antisymmetric gauche, and trans in order of increasing energy, have
been observed. We have successfully assigned ∼7600 pure rotational
transitions within the torsional substates as well as ∼4700
torsional-rotational transitions between the symmetric and
antisymmetric gauche substates through the lower rotational quantum
number J"=68. Spectral lines involving one or both of the two gauche
forms have been simultaneously analyzed with a 2x2 effective
torsional-rotational Hamiltonian, which includes terms through fifth
order in the torsional-rotational interaction. Excluding perturbed
transitions, the assigned transitions were fitted to a root mean
square deviation of 76kHz. The trans substate was analyzed as a
semirigid rotor, and its unperturbed transitions fitted to a root mean
square deviation of 63kHz. A perturbation was seen at transitions with
J">50 in the trans substate. The torsional excitation energy for the
trans substate above ground was estimated from intensity ratios to be
about 120K.
Description:
The Fast Scan Submillimeter-wave Spectroscopic Technique (FASSST)
spectrometer at the Ohio State University was used for the present
measurements.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 47 12598 Rotational-torsional transition frequencies for
iso-propanol in its ground vibrational states
table4.dat 57 17107 Predicted rotational-torsional transition
frequencies for iso-propanol in its ground
vibrational state
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- J' The upper J quantum number
4- 5 I2 --- Ka' The upper Ka quantum number
7- 8 I2 --- Kc' The upper Kc quantum number
10- 11 I2 --- sigma' The upper torsional state (1)
13- 14 I2 --- J" The lower J quantum number
16- 17 I2 --- Ka" The lower Ka quantum number
19- 20 I2 --- Kc" The lower Kc quantum number
22- 23 I2 --- sigma" The lower torsional state (1)
25- 34 F10.3 MHz Freq The experimental frequency of the transition
36- 41 F6.3 MHz O-C The observed minus calculated value
43- 47 A5 --- Comm Additional comments (2)
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Note (1): Torsinal state as follows:
0 = gauche (s)
1 = gauche (a)
2 = trans
Note (2): The indices indicate the source of the transitions:
S1 = microwave/millimeter-wave study of Hirota
(1979, J. Phys. Chem., 83, 1457)
S2 = millimeter-wave study of Ulenikov et al.
(1991, J. Mol. Spectrosc., 145, 265)
S3 = this work
B = blended lines
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- J' The upper J quantum number
4- 5 I2 --- Ka' The upper Ka quantum number
7- 8 I2 --- Kc' The upper Kc quantum number
11 I1 --- sigma' [0/2] The upper torsional state
13- 14 I2 --- J" The lower J quantum number
16- 17 I2 --- Ka" The lower Ka quantum number
19- 20 I2 --- Kc" The lower Kc quantum number
23 I1 --- sigma" [0/2] The lower torsional state
25- 34 F10.3 MHz Freq The frequency of the transition
36- 40 F5.3 MHz e_Freq Estimated uncertainty in Freq
42- 47 F6.3 D2 LineStr Line strength times µG2 (1)
49 A1 --- G Dipole moment component label (2)
51- 57 F7.3 K Eupper/K Upper state energy
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Note (1): Dipole moment values used in calculation are
|<σ=0|µa|σ=1>|=1.11D, µb=0.737D,
µc=0.813D for σ=0 or 1, and µa=0.00D,
µb=1.40D, and µc=0.73D for σ=2.
Note (2): A lower case a, b, c or x designating a-, b-, c-type or
perturbation-allowed x-type transitions.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 29-May-2008