The imidogen radical is an important molecule of the chemistry of nitrogen in the interstellar medium and is thought to be a key intermediate in the gas-phase synthesis of ammonia. The full fine structure of the N = 1 ← 0 rotational transition of 15NH has been observed for the first time by pure rotational spectroscopy around 1 THz. The radical has been produced by means of low-pressure glow discharge of H2 and 15N-enriched nitrogen. A number of hyperfine components have been observed and accurately measured. The analysis of the data provided very precise spectroscopic constants, which include rotational, centrifugal distortion, electron spin-spin interaction, and electron spin-rotation terms in addition to the hyperfine parameters relative to the isotropic and anisotropic electron spin-nuclear spin interactions for 15N and H and to the nuclear spin-rotation for 15N. The efficiency of the discharge system allowed us to observe several components of the same rotational transition in the excited vibrational state v=1, for which a set of spectroscopic constants has also been determined.
Accurate Laboratory Measurement of the Complete Fine Structure of the N = 1 - 0 Transition of 15NH / Bizzocchi, Luca; Melosso, Mattia; Dore, Luca; Esposti, Claudio Degli; Tamassia, Filippo; Prudenzano, Domenico; Lattanzi, Valerio; Laas, Jacob; Spezzano, Silvia; Giuliano, Barbara M.; Endres, Christian P.; Caselli, Paola. - In: THE ASTROPHYSICAL JOURNAL. - ISSN 0004-637X. - ELETTRONICO. - 863:1(2018), pp. 3.1-3.7. [10.3847/1538-4357/aacffc]
Accurate Laboratory Measurement of the Complete Fine Structure of the N = 1 - 0 Transition of 15NH
Bizzocchi, Luca
;Melosso, Mattia;Dore, Luca;Esposti, Claudio Degli;Tamassia, Filippo;
2018
Abstract
The imidogen radical is an important molecule of the chemistry of nitrogen in the interstellar medium and is thought to be a key intermediate in the gas-phase synthesis of ammonia. The full fine structure of the N = 1 ← 0 rotational transition of 15NH has been observed for the first time by pure rotational spectroscopy around 1 THz. The radical has been produced by means of low-pressure glow discharge of H2 and 15N-enriched nitrogen. A number of hyperfine components have been observed and accurately measured. The analysis of the data provided very precise spectroscopic constants, which include rotational, centrifugal distortion, electron spin-spin interaction, and electron spin-rotation terms in addition to the hyperfine parameters relative to the isotropic and anisotropic electron spin-nuclear spin interactions for 15N and H and to the nuclear spin-rotation for 15N. The efficiency of the discharge system allowed us to observe several components of the same rotational transition in the excited vibrational state v=1, for which a set of spectroscopic constants has also been determined.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.