TITLE

Microwave spectrum, large-amplitude motions, and ab initio calculations for N2O5

AUTHOR(S)
Grabow, J.-U.; Andrews, A. M.; Fraser, G. T.; Irikura, K. K.; Suenram, R. D.; Lovas, F. J.; Lafferty, W. J.; Domenech, J. L.
PUB. DATE
November 1996
SOURCE
Journal of Chemical Physics;11/1/1996, Vol. 105 Issue 17, p7249
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The rotational spectrum of dinitrogen pentoxide (N2O5) has been investigated between 8 to 25 GHz at a rotational temperature of ∼2.5 K using a pulsed-molecular-beam Fourier-transform microwave spectrometer. Two weak b-dipole spectra are observed for two internal-rotor states of the molecule, with each spectrum poorly characterized by an asymmetric-rotor Hamiltonian. The observation of only b-type transitions is consistent with the earlier electron-diffraction results of McClelland et al. [J. Am. Chem. Soc. 105, 3789 (1983)] which give a C2 symmetry molecule with the b inertial axis coincident with the C2 axis. Analysis of the 14N nuclear hyperfine structure demonstrates that the two nitrogen nuclei occupy either structurally equivalent positions or are interchanging inequivalent structural positions via tunneling or internal rotation at a rate larger than ∼1 MHz. For the two internal rotor states, rotational levels with Ka+Kc even have IN=0, 2, while levels with Ka+Kc odd have IN=1, where IN is the resultant nitrogen nuclear spin. This observation establishes that the equilibrium configuration of the molecule has a twofold axis of symmetry. Guided by ab initio and dynamical calculations which show a planar configuration is energetically unfavorable, we assign the spectrum to the symmetric and antisymmetric tunneling states of a C2 symmetry N2O5 with internal rotation tunneling of the two NO2 groups via a geared rotation about their respective C2 axes. Because of the Bose–Einstein statistics of the spin-zero oxygen nuclei, which require that the rotational–vibrational–tunneling wave functions be symmetric for interchange of the O nuclei, only four of the ten vibrational-rotational-tunneling states of the molecule have nonzero statistical weights. Model dynamical calculations suggest that the internal-rotation potential is significantly more isotropic than implied by the electron-diffraction analysis. © 1996 American...
ACCESSION #
7619990

 

Related Articles

  • An investigation of the trimethylammonium chloride molecule in the vapor phase by pulsed-nozzle, Fourier-transform microwave spectroscopy. Legon, A. C.; Rego, C. A. // Journal of Chemical Physics;6/15/1989, Vol. 90 Issue 12, p6867 

    The ground-state rotational spectra of the symmetric-top isotopomers [(CH3)314N, H35Cl], [(CH3)314N, D35Cl], [(CH3)315N, H35Cl], and [(CH3)315N, H37Cl] of a dimer formed between trimethylamine and hydrogen chloride have been observed in the vapor above heated samples of solid trimethylammonium...

  • Tunneling motions of argon on chlorofluoromethane. Ottaviani, Paolo; Caminati, Walther; Grabow, Jens-Uwe // Journal of Chemical Physics;11/21/2006, Vol. 125 Issue 19, p194302 

    The rotational supersonic jet Fourier transform microwave spectra of the 35Cl and 37Cl species of the molecular complex chlorofluoromethane-argon show that, in its equilibrium conformation, the argon atom is located out of the ClCF plane, interacting with the F and Cl atoms. All rotational...

  • The microwave spectrum of a two-top peptide mimetic: The N-acetyl alanine methyl ester molecule. Plusquellic, David F.; Kleiner, Isabelle; Demaison, Jean; Suenram, Richard D.; Lavrich, Richard J.; Lovas, Frank J.; Fraser, Gerald T.; Ilyushin, Vadim V. // Journal of Chemical Physics;9/14/2006, Vol. 125 Issue 10, p104312 

    The rotational spectrum of N-acetyl alanine methyl ester, a derivative of the biomimetic, N-acetyl alanine N′-methyl amide or alanine dipeptide, has been measured using a mini Fourier transform spectrometer between 9 and 25 GHz as part of a project undertaken to determine the...

  • High-resolution rotational spectroscopy of the carbon chain anions C3N-, C4H-, and C4D-. McCarthy, M. C.; Thaddeus, P. // Journal of Chemical Physics;8/7/2008, Vol. 129 Issue 5, p054314 

    The rotational spectra of C3N-, C4H-, and C4D- have been measured at high-spectral resolution by Fourier transform microwave spectroscopy. For both C3N- and C4D-, hyperfine structure in the lowest-J transitions has been resolved and measured to better than 0.1 ppm. The quadrupole coupling...

  • Vibrational excitation and relaxation of five polyatomic molecules in an electrical discharge. Sanz, M. Eugenia; McCarthy, Michael C.; Thaddeus, Patrick // Journal of Chemical Physics;5/15/2005, Vol. 122 Issue 19, p194319 

    Vibrational excitation and relaxation of five linear polyatomic molecules, OCS, OC3S, HC3N, HC5N, and SiC2S, have been studied by Fourier transform microwave spectroscopy in a supersonic expansion after the application of a low-current dc electric discharge. For each chain, the populations in...

  • Fourier transform microwave spectroscopy of the CH[sub 2]CP(XËœ [sup 2]B[sub 1]) radical. Ozeki, H.; Habara, H.; Ahmad, I. K.; Saito, S.; Yamamoto, S. // Journal of Chemical Physics;9/22/2002, Vol. 117 Issue 12, p5670 

    The hyperfine resolved rotational spectrum of the CH[sub 2]CP radical in the &Xtilde;²B[sub 1] ground electronic state has been observed for the first time using a Fourier transform microwave spectrometer in combination with a pulsed discharge nozzle. The radical was produced by discharging a...

  • Excited ν3 vibrational state of the Ar–HCN and Kr–HCN dimers. Arunan, E.; Emilsson, T.; Gutowsky, H. S. // Journal of Chemical Physics;7/8/1995, Vol. 103 Issue 2, p493 

    Rotational spectra have been observed for an excited vibrational state of the Ar/Kr–HCN dimers in a Balle–Flygare Fourier transform microwave spectrometer with a high temperature nozzle that can be heated to ∼1300 K. The B, DJ, and HJ rotational constants found for the excited...

  • Microwave spectra and structures of the NNO–HCN, 15NNO–HCN, and NNO–DCN complexes. Pauley, D. J.; Kukolich, S. G. // Journal of Chemical Physics;9/15/1990, Vol. 93 Issue 6, p3881 

    A total of 60 a- and b-dipole rotational transitions were measured in the 4–18 GHz range for the NNO–HCN, 15NNO–HCN, and NNO–DCN bimolecular complexes using a pulsed-beam, Fourier transform microwave spectrometer. Spectroscopic constants (A-DK), B, C, DJ, DJK, eQqaa...

  • Fourier-transform microwave spectroscopy of triplet carbon monoxides, C2O, C4O, C6O, and C8O. Ohshima, Yasuhiro; Endo, Yasuki; Ogata, Teruhiko // Journal of Chemical Physics;1/22/1995, Vol. 102 Issue 4, p1493 

    Rotational spectra of CnO with n=2, 4, 6, and 8 have been observed by using a Fabry–Perot type Fourier-transform microwave spectrometer cooperated with a pulsed discharge nozzle. The molecules have been generated by an electric discharge of carbon suboxide diluted in Ar, and adiabatically...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics