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Version 2021.08.hfs
Tag 31802
Molecule - Descriptor Methylamine, Methanamine (CH3NH2) - v=0
Isotope parent
Hyperfine Yes
Lines in DB 140452
Frequency max. (MHz) 2999616.736
J max. 50
Cite these data as Motiyenko R.A., Ilyushin V.V., Drouin B.J., Yu S., Margulès L. 2014, A&A, 563, A137 https://doi.org/10.1051/0004-6361/201323190
Predictions Partition Function Quantum Numbers Format References

T(K) Qt Qrot Qvib
300.0 93538.290 93538.29 1.0
200.0 50881.290 50881.29 1.0
150.0 33035.760 33035.76 1.0
50.0 6349.680 6349.68 1.0
10.0 566.820 566.82 1.0

Methylamine vibration-rotation-tunneling energy levels in the Ohashi-Hougen formalism

Code:
Ohashi-Ilyushin code for methylamine
Output Format:
J K Sym F

Details: Each energy level is characterized by the quantum numbers J and K = Ka, together with the overall torsion–wagging–rotation symmetry species Γ, corresponding to an irreducible representation of the permutation–inversion group G12. To distinguish between the two components of doubly degenerate levels of E1 or E2 symmetry with identical J and K values, the labels E1+1 and E1−1, or E2+1 and E2−1 are employed, where the +1 and −1 components correspond to k = +K and k = −K, respectively. When table includes hyperfine levels, the standard quantum number F = J + I is included in the level designation.

The correspondence between the integer symmetry identifier Sym used in the .cat file and the symmetry species Γ is summarized in the table below.

Sym 3 -3 4 -4 1 -1 2 -2
Γ A1 A2 B1 B2 E1+1 E1-1 E2+1 E2-1
Previously published reference data

  • Predicted spectra up to 500 GHz: Ilyushin V., Lovas F.J. 2007, J. Phys. Chem. Ref. Data, 36, 1141–1276
Measurements

  • Ilyushin V.V., Alekseev E.A., Dyubko S.F., Motiyenko R.A., Hougen J.T. 2005, J. Mol. Spec., 229, 170–187
  • Lide Jr D.R. 1954, J. Chem. Phys., 22, 1613–1614
  • Shimoda K., Nishikawa T., Itoh T. 1954, J. Phys. Soc. Jpn., 9, 974–991
  • Hirakawa H., Miyahara A., Shimoda K. 1956, J. Phys. Soc. Jpn., 11, 334–335
  • Nishikawa T. 1957, J. Phys. Soc. Jpn., 12, 668–680
  • Takagi K., Kojima T. 1971, J. Phys. Soc. Jpn., 30, 1145–1157
  • Takagi K., Kojima T. 1973, ApJ, 181, L91
  • Ohashi N., Takagi K., Hougen J.T., Olson W.B., Lafferty W.J. 1987, J. Mol. Spec., 126, 443–459
  • Krȩglewski M., Wlodarczak G. 1992, J. Mol. Spec., 156, 383–389
  • Krȩglewski M., Stahl W., Grabow J.-U., Wlodarczak G. 1992, Chem. Phys. Lett., 196, 155–158
Dipole moments

  • Lide Jr D.R. 1957, J. Chem. Phys., 27, 343–352
  • Takagi K., Kojima T. 1971, J. Phys. Soc. Jpn., 30, 1145–1157