Argonium, 1Σ+, 40Ar isotopic species
Species tag 041504
Date of EntrySep. 2007
ContributorH. S. P. Müller

Pure rotational as well as rovibrational data of several isotopic species of ArH+ have been fit simultaneously.
The J = 1 – 0 transition frequency was reported in
(1) K. B. Laughlin, G. A. Blake, R. C. Cohen, D. C. Hovde, and R. J. Saykally, 1987, Phys. Rev. Lett., 58, 996.
Additional lines up to J = 7 – 6 were taken from
(2) J. M. Brown, D. A. Jennings, M. Vanek, L. R. Zink, and K. Evenson, 1988, J. Mol. Spectrosc. 128, 587.
The J = 1 – 0 transition frequencies of three ArD+ isotopic species involving 40Ar, 36Ar, and 38Ar, were published by
(3) W. C. Bowman, G. M. Plummer, E. Herbst, and F. C. De Lucia, 1983, J. Chem. Phys. 79, 2093;
the reported uncertainties for the 40Ar and 36Ar species have been increased somewhat.
High-J pure rotational transition frequencies of ArD+ were taken from
H. Odashima, A. Kozato, F. Matsushima, S. Tsunekawa, and K. Takagi, 1999, J. Mol. Spectrosc. 195, 356.
High-J pure rotational transitions of ArH+ up to high vibrational states were detected in the lower infrared region by
(5) D. J. Liu, W. C. Ho, and T. Oka, 1987, J. Chem. Phys. 87, 2442.
Rovibrational transitions of ArH+ were recorded by
(6) J. W. Brault and S. P. Davis, 1982, Physica Scripta 25, 268.
Additional high-v transitions as well as transitions of ArD+ were reported by
(7) J. W. C. Johns, 1984, J. Mol. Spectrosc. 106, 124.
Infrared data for 36ArH+ and 38ArH+ was provided by
(8) R. R. Filueira and C. E. Blom, 1988, J. Mol. Spectrosc. 127, 279.
There is great consistency among essentially all experimental data. Therefore, it may well be that ion drift effects on the reported frequencies are small. Nevertheless, all predictions should be viewed with some caution, especially if the calculated uncertainties exceed 2 MHz by far.
Experimental transitions frequencies with uncertainties larger than 200 kHz have not been merged.
The dominant intersteller argon isotope is 36Ar. The by far dominant isotope on Earth is 40Ar, but it originates almost entirely from the radioactive decay of 40K. Its relative abundance in the ISM is almost negligible.
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.
The ground state ab initio dipole moment was taken from
(9) M. Cheng, J. M. Brown, P. Rosmus, R. Linguerri, N. Komiha, and E. G. Myers, 2007, Phys. Rev. A 70, Art. No. 012502.

Lines Listed30
Frequency / GHz< 16540
Max. J30
log STR0-18.0
log STR1-18.0
Isotope Corr.-0.0
Egy / (cm–1)0.0
 µa / D2.177
 µb / D 
 µc / D 
 Q(1000.)70.3236 (68.5556, 1.7152, 0.0510, 0.0018)
 Q(500.0)34.3246 (34.3039, 0.0207)
 Q(300.0)20.6843 (20.6842, 0.0001)
 Q(225.0)15.5890 (15.5890)
 Q(150.0)10.5013 (10.5013)
 Q(75.00)5.4245 (5.4245)
 Q(37.50)2.8998 (2.8998)
 Q(18.75)1.6650 (1.6650)
 Q(9.375)1.1286 (1.1286)
detected in ISM/CSMno

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