The experimental frequencies have been reported by
(1) S. Thorwirth, H. S. P. Müller, and G. Winnewisser, 2001, Phys. Chem. Chem. Phys. 3, 1236.
The parameter l_JL was kept fixed to the value determined for the main isotopic species.
Mar. 2012: The individual states have been set up differently to describe the parity of the state l = 2^– correctly. Now state number 0 refers to l = 0⁺, state number 1 to l = 0^–, and state number 2 to l = 2. Version number and date of entry have been retained.
As can be seen in (1), the Hamiltonian converges slowly. This is probably caused by the rotational interaction with v₇ = 3. Predictions should be viewed with caution above 800 GHz.
Vibrational contributions to the partition function of HCC¹³CN are also available.
The dipole moment was assumed to agree with that of the main isotopolog, see e051505.cat.