Details of the global fit involving several isotopomers are available in
(1) H. S. P. Müller, F. Schlöder, J. Stutzki, and G. Winnewisser, 2005, J. Mol. Struct. 742, 215.
The pure rotational lines were taken from
(2) M. Bogey, C. Demuynck, and J. L. Destombes, 1981, Chem. Phys. Lett., 81, 256; from
(3) M. Bogey, C. Demuynck, and J. L. Destombes, 1982, J. Mol. Spectrosc., 95, 35; from
(4) V. Ahrens and G. Winnewisser, 1999, Z. Naturforsch. 54a, 131;
(5) E. Kim and S. Yamamoto, 2003, J. Mol. Spectrosc., 219, 296; and from
(6) C. A. Gottlieb, P. C. Myers, and P. Thaddeus 2003, Astrophys. J., 588, 655. Infrared transitions v = 1 – 0 for several isotopomers and v = 2 – 1 for the main isotopomer by
(7) J. B. Burkholder, E. R. Lovejoy, P. D. Hammer, and C. J. Howard 1987, J. Mol. Spectrosc. 124, 450;
v = 1 – 0 to v = 9 – 8 of the main isotopomer by
(8) R. S. Ram, P. F. Bernath, and S. P. Davies, 1995, J. Mol. Spectrosc. 173, 146;
and v = 2 – 0 of the main isotopomer by
(9) R. J. Winkel, Jr., S. P. Davies, R. Pecyner, and J. W. Brault; 1984, Can. J. Phys. 62, 1414
were also used in the fit.
In general, lines deviating from their calculated position by more than 2.5 times their uncertainties have been omitted from the final fit. For the main isotopomer, the uncertainty of the J = 3 – 2 line from (5) has been doubled.
It should be pointed out that the precision of the infrared transitions is 0.003 cm^–1 or 9 MHz for lower vibrational bands, the accuracy may be somewhat smaller. With this in mind, the predictions should be rather reliable throughout.
The transition dipole moments were calculated ab initio by
(10) P. Botschwina and P. Sebald, 1985, J. Mol. Spectrosc. 110, 1.
All vibrational states used in the fit have been considered for the calculation of the partition function. Contributions of the individual vibrations are given in parentheses.