Neonium, 1Σ+
Species tag 021501
Date of EntryDec. 2007
ContributorH. S. P. Müller

Pure rotational as well as rovibrational data of several isotopic species of NeH+ have been fit simultaneously.
Several pure rotational transition frequencies were reported in
(1) F. Matsushima, Y. Ohtaki, O. Torige, and K. Takagi, 1998, J. Chem. Phys., 109, 2242.
These data could not be reproduced within the reported experimental uncertainties. As in (1), the transitions of 22NeH+ deviated most with respect to the uncertainties. Trial fits showed that the omission of the two higher-J transitions of this species gave a rather satisfactory fit.
An additional high-J line was published by
(2) D. J. Liu, W. C. Ho, and T. Oka, 1987, J. Chem. Phys. 87, 2442.
Rovibrational transitions of NeH+ were recorded by
(3) M. Wong, P. Bernath, and T. Amano, 1982, J. Chem. Phys. 77, 693;
(4) R. S. Ram, P. F. Bernath, and J. W. Brault, 1985, J. Mol. Spectrosc. 113, 451
and by
(5) S. Civis, J. Sebera, V. Spirko, J. Fiser, W. P. Kraemer, and K. Kawaguchi, 2004, J. Mol. Struct. 695–696, 5.
Some transitions from (4) and (5) were omitted from the fits because of large and irregular residuals. Moreover, the vibrational expansion of the Dunham-type expansion requires many higher order terms; a direct potential fit probably would have been advantageous. Thus, the very weak v = 4 – 3 transitions from (5) were also not included in the fit.
The amount of ion drift effects on the reported frequencies are difficults to estimate. Thus, all predictions should be viewed with some caution, in particular those above 10 THz.
Experimental transitions frequencies with uncertainties larger than 300 kHz have not been merged.
The ab initio dipole moment was taken from
(6) M. Cheng, J. M. Brown, P. Rosmus, R. Linguerri, N. Komiha, and E. G. Myers, 2007, Phys. Rev. A 70, Art. No. 012502.
The partition function takes into account all vibrational states used in the fit. Non-zero contributions of individual vibrational states to the partition function are given in parentheses.

Lines Listed23
Frequency / GHz< 20109
Max. J23
log STR0-17.0
log STR1-17.0
Isotope Corr.-0.0435
Egy / (cm–1)0.0
 µa / D3.005
 µb / D 
 µc / D 
 Q(1000.)41.8954 (40.9373, 0.9276, 0.0292, 0.0013)
 Q(500.0)20.5166 (20.5068, 0.0098)
 Q(300.0)12.4103 (12.4103)
 Q(225.0)9.3858 (9.3858)
 Q(150.0)6.3691 (6.3691)
 Q(75.00)3.3664 (3.3664)
 Q(37.50)1.8886 (1.8886)
 Q(18.75)1.2115 (1.2115)
 Q(9.375)1.0147 (1.0147)
detected in ISM/CSMno

Database maintained by Holger S. P. Müller and Sven Thorwirth, programming by D. Roth and F. Schloeder