Introduction
The OH+ fit was described in the following publication:
(1) H. S. P. Müller, F. Schlöder, J. Stutzki, and G. Winnewisser,
The Cologne Database for Molecular Spectroscopy, CDMS:
a useful tool for astronomers and spectroscopists,
J. Mol. Struct. 742, 215227 (2005).
View the abstract.
The OH+ data were taken from the following publications:
N = 1 0 with FS and HFS:
J. P. Bekooy, P. Verhoeve, W. Leo Meerts, and A. Dymanus,
Submillimeter spectroscopy on OH+:
The rotational transition at 1 THz,
J. Chem. Phys. 82, 38683869 (1985).
N = 13 12 with FS:
D.-J. Liu, W.-C. Ho, and T. Oka,
Rotational spectroscopy of molecular ions using diode lasers,
J. Chem. Phys. 87, 24422446 (1987).
View the abstract.
Vibration-rotation transitions up to
v = 5 4 with FS:
B. D. Rehfuss, M.-F. Jagod, L.-W. Xu, and T. Oka,
Infrared spectroscopy of highly excited vibrational levels
of the hydroxyl ion, OH+,
J. Mol. Spectrosc. 151, 5970 (1992).
View the abstract.
The Parameter File
is setup fairly straightforwardly. States 0-5 represent
v = 0 - 5 with fine structure splitting.
State 6 codes v = 0 with fine and hyperfine
structure splitting.
Because of the different degrees of splitting (with FS and with
FS and HFS, respectively) there are 2 option lines !
The parameter ratios for the various states have to be given explicitely for
all of the Yi,j. If there is only one isotopic species,
this is not necessary for i = 0 !
Remarks on the Quantum Numbers
N, v, J, and F are the quantum numbers. One should be aware of v being a state number representing vibrational quanta only in part. F is not needed for the description of states 0-5, however, F = J has to be used in the line file !
Extrapolation to Higher Quantum Numbers
should always be viewed with caution ! Because of the many infrared transitions used in the fit it is conceivable that the predictions are reliable for low values of N and fairly reliable for higher values of N. In addition, ΔF = ΔJ = ΔN should hold ! "Reliable prediction" means that the transition will be found within three to ten times the predicted uncertainty.