Details

Autor(en) / Beteiligte

• Fichoux, H.
• Khelkhal, M.
• Rusinek, E.
• Legrand, J.
• Herlemont, F.
• Urban, Š.

Titel

Double Resonance Sub-Doppler Study of the Allowed and ΔK = −3ForbiddenQ(3, 3)Transitions to the ν2Vibrational State of14NH3

Ist Teil von

• Journal of molecular spectroscopy, 1998-11, Vol.192 (1), p.169-178

Ort / Verlag

Elsevier Inc

Erscheinungsjahr

1998

Quelle

ScienceDirect

Beschreibungen/Notizen

• The IR–IR sub-Doppler double resonance and standard saturation sideband spectroscopy have been used to measure the allowed and Δk = −3 forbidden transitions to the ν2vibrational level of14NH3. The IR–IR double resonance technique has made it possible to observe quadrupole hyperfine structures which correspond to the sums as well as differences of the−3Q(3, 3) and Q(3, 3) hyperfine components. The “sum” and “difference” double resonance frequencies have been measured with accuracy better than 30 and 5 kHz, respectively. In addition to this, the hyperfine structure of the allowed Q(3, 3) transition has been independently measured using the “standard” saturation sideband spectroscopy with accuracy better than 15 kHz. A simultaneous analysis of all measured data provides an improved set of effective nuclear quadrupole and spin–rotation parameters for the excited ν2vibrational state and frequencies of the “pure” rotation–vibration transitions deperturbed from the hyperfine effects at the experimental sample pressure of about 3 mTorr, including a very precise zero pressure value of the “forbidden” spacing between energies of the ν2‖s, J = 3, K = 3〉 and ‖s, J = 3, K = 0〉 pure rotational levels of 2883.6795(19) MHz [0.096189194(63) cm−1].