The pure rotational data have been reported by
(1) Y. Kawashima, Y. Endo, K.Kawaguchi, and E. Hirota, 1987, Chem. Phys. Lett. 135, 441;
one additional transition was reported in
(2) Y. Kawashima, Y. Endo, and E. Hirota, 1989, J. Mol. Spectrosc. 133, 116.
Even though ¹⁰B hyperfine structure was resolved only in the J = 2 – 1, the apparent line maxima are somewhat different from the hyperfine-free line centers, though only slightly for only up to J = 5 – 4. Therefore, no transitions have been merged.
The predictions are deemed to be reliable up to about 1.0 THz, possibly higher.
At low J, it is possible to resolve the ¹⁰B hyperfine splitting. Therefore, a separate hyperfine calculation up to J' = 5 is provided. Note: The partion function given below takes into account this splitting !
The dipole moment was assumed to agree with that of the main species, see e028514.cat.