The experimental millimeter and lower submillimeter lines are from
(1) J. Tang, and S. Saito, 1996, J. Chem. Phys. 105, 8020.
Additional lower frequency data with hyperfine structure splitting were taken from
(2) E. Kim, H. Habara, and S. Yamamoto, 2002, J. Mol. Spectrosc. 212, 83.
The spin-orbit splitting was taken from
(3) S.-G. He and D. C. Clouthier, 2005, J. Chem. Phys. 123, Art. No. 014317.
The calculation should be reliable throughout. Slight caution may be advisable at frequencies higher than 400 GHz.
The ²H hyperfine splitting may be resolved for lower J transitions. Therefore, a separate hyperfine calculation up to J' = 4.5 is provided. The ²H spin multiplicity of 3 was considered in the calculation of the partition function !
The dipole moment is from an ab initio calculation from
(4) C. Puzzarini, 2008, Chem. Phys. 346, 45.