Scientific Results

High sensitivity CW-cavity ring down spectroscopy of N2O near 1.5 µm (I)

Year: 2007

Authors: Liu A.W., Kassi S., Malara P., Romanini D., Perevalov V.I., Tashkun S.A., Hu S.M., Campargue A.

Autors Affiliation: Laboratoire de Spectrometrie Physique (associated with CNRS, UMR 5588), Universite´ Joseph Fourier de Grenoble, B.P. 87, 38402 Saint-Martin-d’He`res Cedex, France; Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei 230026, China; CNR – Istituto Nazionale di Ottica Applicata (INOA), Comprensorio ‘A.Olivetti’, Via Campi Flegrei 34, 80078 Pozzuoli (Naples), Italy; Laboratory of Theoretical Spectroscopy, Institute of Atmospheric Optics, SB, Russian Academy of Science, 1, Akademicheckii av., 634055, Tomsk, Russia

Abstract: The absorption spectrum of nitrous oxide, N2O, in natural isotopic abundance has been recorded by CW-Cavity Ring Down Spectroscopy between 6000 and 6833 cm(-1). The spectra were obtained at Doppler limited resolution by using a CW-CRDS spectrometer based on a series of fibered DFB lasers. The typical sensitivity of 2 x 10(-10) cm(-1), allowed for the detection of lines with intensity as weak as 2 x 10(-29) cm/molecule while the minimum intensity value provided by HITRAN in the considered spectral region is 2 x 10(-25) cm/mol- ecule. More than 6000 line positions of five isotopologues contributing to the spectra ((N2O)-N-14-O-16, (NNO)-N-15-N-14-O-16, (NNO)-N-14-N-15-O-16, (N2O)-N-14-O-18 and (N2O)-N-14-O-17), were measured with a typical accuracy of 1.5 x 10(-3) cm(-1) and rovibrationally assigned on the basis of their respective global effective Hamiltonian models. Highly excited rovibrational levels corresponding to J values larger than 80 could be detected for the stronger vibrational bands. The band by band analysis led to the determination of the rovibrational parameters of a total of 68 bands, 49 of them being newly reported. The rms value of the deviations of the predictions of the effective Hamiltonian models from the observed line positions is 0.010 cm(-1). As expected, the quality of the predictions degrades for the minor isotopologues for which important deviations up to a few wavenumbers were evidenced. Most of the bands were found unperturbed but in a few cases, local rovibrational perturbations were evidenced. The interaction mechanisms and the perturbers were univocally assigned on the basis of the effective Hamiltonian model. In particular, interpolyad couplings were evidenced indicating that the polyad version of the effective Hamiltonian has to be extended to include Coriolis and interpolyad anharmonic interactions. (C) 2007 Elsevier Inc. All rights reserved.

Journal/Review: JOURNAL OF MOLECULAR SPECTROSCOPY

Volume: 244 (1)      Pages from: 33  to: 47

More Information: This work, performed in the frame of the European research network QUASAAR (MRTN-CT-2004-512202), is jointly supported by a collaborative project between CNRS-France and RFBR-Russia (PICS Grant No 05-05-22001) and between CNRS and CAS-China (PICS Grant No 3359). The support of the Programme National LEFE (CHAT) INSU-CNRS is acknowledged. Appendix A
KeyWords: 1.5 µm atmospheric window; Cavity ring down spectroscopy; CRDS; Effective Hamiltonian model; N2O; Near infrared; Nitrous oxide; Distributed feedback lasers; Hamiltonians; Mathematical models; Spectrometers; Spectroscopic analysis, Anharmonic interactions; Vibrational bands; Wavenumbers; Nitrogen compounds
DOI: 10.1016/j.jms.2007.01.007

Citations: 26
data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2021-08-01
References taken from IsiWeb of Knowledge: (subscribers only)
Connecting to view paper tab on IsiWeb: Click here
Connecting to view citations from IsiWeb: Click here