HC3N, (1,0,0,0)
Cyanoacetylene, Propynenitrile, v4 = 1
Species tag 051506
Version2*
Date of EntryApr. 2012
ContributorH. S. P. Müller

The (1,0,0,0) state undergoes anharmonic, non-resonant interaction with the (0,0,2,0), (0,0,0,4), and (0,1,0,1) states. Moreover, the latter two states are in resonant interaction. The present entry takes all these interactions into account, in contrast to the first entry from Oct. 2000. The interactions among these states have been analyzed for the first time by
(1) K. M. T. Yamada and R. A. Creswell, 1986 J. Mol. Spectrosc. 116, 384.
A considerable amount of transition frequencies were taken from that work. Additional data were taken from
(2) L. Mbosei, A. Fayt, P. Dréan, and J. Cosléou, 2000, J. Mol. Struct. 517-518, 271.
Additional data for v4 = 1 were reported by
(3) S. Thorwirth, H. S. P. Müller, and G. Winnewisser, 2000, J. Mol. Spectrosc. 204, 133;
and by
(4) P. D. Mallinson and R. L. de Zafra, 1978, Mol. Phys. 36, 827.
The present analysis follows largely (1); some additional parameters were estimated from the data in (3). The ν4 band origin has not been determined with accuracy. An estimate was taken from
(5) P. D. Mallinson and A. Fayt, 1976, Mol. Phys. 32, 473.
This value has been reproduced not particularly well because of the large uncertainty. The 2 ν6 and ν5 + ν7 band origins were derived from
(6) E. Arie, Dang Nhu M., Ph. Arcas, G. Graner, H. Bürger, G. Pawelke, M. Khilfi, and F. Raulin, 1990, J. Mol. Spectrosc. 143, 318.
Possible rotational (Coriolis-type) interaction of (0,0,1,2) with (0,0,2,0) or with (0,0,0,4) has been neglected in the present analysis. Redundant quantum numbers have been omitted. Transition frequencies with uncertainties larger than 100 kHz have not been merged.
The predictions are deemd to be reliable throughout.
Note: The partition function does not include any vibrational corrections. However, vibrational contributions to the partition function of HC3N are available.
The dipole moments were estimated or derived from those of the (0,0,0,0), (0,0,0,1), and (0,0,1,0) states.

Lines Listed112
Frequency / GHz1015
Max. J112
log STR0-7.5
log STR1-6.0
Isotope Corr.0.0
Egy / cm–1~863.5
 µa / D3.730
 µb / D 
 µc / D 
 A / MHz 
 B / MHz4538.24
 C / MHz 
 Q(300.0)1374.9098
 Q(225.0)1031.1809
 Q(150.0)687.5086
 Q(75.00)343.8929
 Q(37.50)172.1063
 Q(18.75)86.2186
 Q(9.375)43.2767
detected in ISM/CSMyes


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