Ethynyl, X 2Σ+; isotopolog with 13C on C2
Species tag 026503
Date of EntryJan. 2010
ContributorH. S. P. Müller

The spectrum was described in
(1) M. C. McCarthy, C. A. Gottlieb, and P. Thaddeus, 1995, J. Mol. Spectrosc. 173, 303.
The experimental lines were kindly provided by Dr. McCarthy. Because some lines have residuals substantially larger than the estimated uncertainties, the reduced standard deviation of the fit is 2.5 (see also (1)).
With respect to the May 2000 entry, rest frequencies for the N = 1 – 0 transition from astronomical observations were used in the fit. These were reported by
(2) N. Sakai, O. Saruwatari, T. Sakai, S. Takano, and S. Yamamoto, 2010, Astron. Astrophys.173, accepted.
In addition, γD was kept fixed to the value of the main isotopolog, see e025501.cat. Only data from (2) were merged. It is worthwhile mentioning that the residuals of the remaining data from (1), though in part much larger than the estimated uncertainties, did not exceed 150 kHz.
The predictions are probably reliable up to 1.0 or 1.2 THz.
The dipole moment is assumed to the same as for the main isotopolog, see e025501.cat.

Lines Listed247
Frequency / GHz< 2379
Max. J28
log STR0-8.5
log STR1-4.5
Isotope Corr.-1.955
Egy / (cm–1)0.0
 µa / D0.770
 µb / D 
 µc / D 
detected in ISM/CSMyes

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