13CH3OH, vt = 0, 1
Methanol, 13C isotopomer, vt = 0, 1
Species tag 033502*
Date of EntryDec. 2002
ContributorsL.-H. Xu
H. S. P. Müller

The entry is based on a line list file provided by L.-H. Xu from the review
(1) L.-H. Xu and F. J. Lovas, 1997, J. Phys. Chem. Ref. Data 26, 17.
Details on the RAM (RHO axis method) and fitting program employed to reduce the data is available in
(2) L.-H. Xu, M. S. Walsh, and R. M. Lees, 1996, J. Mol. Spectrosc. 179, 269 and references therein.
These two papers also give details on the extensive data sets considered in the fits. Because of the internal rotation (torsion), torsion-rotation interaction, and large effects of centrifugal distortion, global modeling of the methanol spectrum is a challenging task. Nevertheless, restricting the data set to vt = 0, 1, Jmax = 20, and Kmax = 14, the input data was reproduced within experimental uncertainties. Very small experimental uncertainties have been set to 50 kHz for most of the microwave lines in the fit.
Certain prediction, in particular those of higher J, may be found outside three times the uncertainties. However, because of the large body of transitions observed by FTFIR spectroscopy, it is expected that these deviations are within 6 MHz, an uncertainty value assigned to the FTFIR data).
Note: Currently the base 10 logarithm of Sg μg2, which is temperature independent, is given instead of the base 10 logarithm of the intensity at 300 K !
The quantum numbers given are those of (1) and (2), but slightly rearranged for lay-out reasons. They are
J, (sign)Ka, Kc, (parity), immediately followed by vt.
The parities + and – refer to A+ and A – states; while states with no parity designation refer to E symmetry. A signed value of Ka is used to differentiate (+)E1 from (–)E2 states. It should be emphasized that E1 and E2 states belong to the same E symmetry species.
As usual, the energies in the catalog entry are given with respect to the lowest rotational level (000 of the vt = 0, A state) which is defined as zero.
The energies given in the documentation refer to the 000 rotational levels of the
vt = 0, A and E states and the vt = 1, E and A states, respectively.
The dipole moment is assumed to be the same as for the main isotopmer, see e032504.cat.
Note: The current entry takes into account contributions of the permanent dipole moment only ! Torsional or rotational dependences as well as changes in the dipole moment with torsional state have not yet been determined – or only to an insufficient amount. The effects of these contributions may be non-negligible in certain instances.

Lines Listed3579
Frequency / GHz< 1000
Max. J26
log STR0 
log STR1 
Isotope Corr.-1.960
Egy / cm-10.000 / 9.111 / 208.972 / 294.458
 µa / D0.899
 µb / D–1.44
 µc / D 
 A / MHz127527.4
 B / MHz24083.5
 C / MHz23197.0
detected in ISM/CSMyes

Database maintained by Holger S. P. Müller and Sven Thorwirth, programming by D. Roth and F. Schloeder