Cyanomethylene, X 3Σ / 3A", D isotopolog
Species tag 040512
Date of EntryJan. 2012
ContributorH. S. P. Müller

HCCN is an asymmetric top molecule with a low barrier to linearity, i.e., it is quasilinear, similar to the parent species methylene, CH2, which is somewhat closer to an asymmetric top rotor.
The experimental lines were reported by
(1) F. X. Brown, S. Saito, and S. Yamamoto, 1990, J. Mol. Spectrosc. 143, 203.
Uncertainties of 20 kHz were used in the fit.
The predictions should be viewed with some caution because of the small data set. Nevertheless, the strong fine structure components may be well predicted down to about 80 GHz and up to about 900 GHz.
Hyperfine splitting due to the 2H and 14N nuclei may broaden the lines below about 120 GHz and may be resolvable at the lowest frequencies.
The dipole moment was assumed to agree with that of the main species, see e039501.cat.

Lines Listed202
Frequency / GHz< 1245
Max. J63
log STR0-6.5
log STR1-3.5
Isotope Corr.-3.821
Egy / (cm–1)0.0
 µa / D3.035
 µb / D 
 µc / D 
detected in ISM/CSMno

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