C12H
Dodecahexaynyl, X 2Πi
Species tag 145501
Version1*
Date of EntryFeb. 2023
ContributorH. S. P. Müller

The experimental transition frequencies were reported by
(1) C. A. Gottlieb, M. C. McCarthy, M. J. Travers, J.-U. Grabow, and P. Thaddeus, 1998, J. Chem. Phys. 109, 5433.
The fit has been carried out using parameters and quantum numbers of Hund's case (b). The highest frequency rotational transition was omitted because of large residuals. The remainder of the lines was deeemed to be uncertain to 1 kHz. No 1H hyperfine splitting was resolved in the laboratory; it may be resolvable for the lowest transitions. Calculations of the upper 2Π1/2 component were omitted because no experimental data are available. Calculations of the lower 2Π3/2 component may be reliable up to about 50 GHz.
Please not that the partition function is not converged at high temperatures, but it should be fine up to about 150 K. The dipole moment has been estimated.

Lines Listed568
Frequency / GHz<100
Max. J285
log STR0-9.5
log STR1-4.5
Isotope Corr. 
Egy / cm–10.0
 µa / D8.5
 µb / D 
 µc / D 
 A / MHz 
 B / MHz174.777
 C / MHz 
 Q(300.0)135384.1797
 Q(225.0)99863.6647
 Q(150.0)64366.2620
 Q(75.00)29317.3400
 Q(37.50)12598.4012
 Q(18.75)5221.0744
 Q(9.375)2301.7623
 Q(5.000)1197.5980
 Q(2.725)653.5803
detected in ISM/CSMno


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