|
Isothiocyanic acid is a pseudolinear molecule with a large
A rotational parameter – analogously to
isocyanic acid, HNCO. The Hamiltonian is very slowly
converging, in particular for the purely K-dependent
terms. Moreover, at higher values of Ka,
there is extensive vibration rotation interaction bewteen
the ground vibrational state of HNCS and its three lowest
excited vibrational states. Only transitions with
Ka = 1 ↔ 0 are
given because others are not only too high in energy,
but can, in addition, not be predicted reliably.
Data were taken from
(1) L. B. Szalanski, M. C. L. Gerry, G. Winnewisser,
K. M. T. Yamada, and M. Winnewisser,
1978, Can. J. Phys. 56, 1297.
The predictions should be quite good as long as
the predicted uncertainties do not exceed 200 kHz.
Note that not only extrapolation to high J
should be viewed with some caution, but also
that to low values of J.
The partition function takes into account
higher Ka values.
The b-dipole moment component was determined in (1).
Because of the large uncertainty of the DNCS value
1.0 D was used as the b-component of HNCS
for simplicity reasons.
A seperate entry is given for the a-type
transitions.
|