Ammonia, triply deuterated isotopomer
Species tag 020501
Date of EntryJune 2002
ContributorH. S. P. Müller

The observed transitions were taken from
(1) P. Helminger and W. Gordy, 1969, Phys. Rev. 188, 100;
(2) P. Helminger, F. C. de Lucia, and W. Gordy, 1971, J. Mol. Spectrosc. 39, 94;
(3) L. Fusina, D. di Lonardo, and J. W. C. Johns, 1985, J. Mol. Spectrosc. 112, 211;
(4) S. N. Murzin, 1985, Opt. Spektrosk. 59, 725
; and from
(5) L. Fusina and S. N. Murzin, 1994, J. Mol. Spectrosc. 167, 464
Using two additional higher order centrifugal distortion constants compared to the constants from (5), it was possible to fit the transition frequencies within experimental uncertainties on the average. The dipole moment was taken from
(6) D. di Lonardo and A. Trombetti, 1981, Chem. Phys. Lett. 84, 327
As for the main isotopomer NH3, ND3 tunnels between two equivalent positions. Transitions occur between the symmetric (s) and antisymmetric (a) substates. The a, J = 0 state is higher than the s, J = 0 state by 0.0531 cm–1 or 1591.6 MHz. In addition, one has to distiguish between A and E state levels with a spin-statistical weight ratio of 11 : 8. The A state levels are described by K = 3n. Moreover, splitting of the A levels into A1 and A2 levels with a spin-statistical weight ratio of 10 : 1 has to be taken into account. For K = 3, this splitting can be resolved. For K = 0, the a – s belong to A1, while the a – s belong to A2. For K = 6 and higher, the splitting is very small; the two transition frequencies have been merged frequently.
For essentially all of the lines only hyperfine free center frequencies were reported. Since 14N hyperfine splitting may be resolved for low values of J, a separate calculation with hyperfine splitting is provided for J up to 3.

Lines Listed698
Frequency / GHz< 7299
Max. J24
log STR0-9.3
log STR1-6.3
Isotope Corr.-11.818
Egy / cm-10.0 / 0.0531
 µa / D 
 µb / D 
 µc / D1.497
 A / MHz= B
 B / MHz154173.3
 C / MHz93673.5
detected in ISM/CSMyes

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