EGAS41 - Swansea University

41 st EGAS CP 81 Gdańsk 2009
Study of charge transfer excitation in collisions of nitrogen ions
with carbon dioxide molecules
B. Pranszke
Institute of Experimental Physics, University of Gdańsk, ul. Wita Stwosza 57,
80-952 Gdańsk, Poland
E-mail: fizbp@univ.gda.pl
Numerous papers were dedicated to the CO 2 -molecule reactions in the past four decades
[1], primarily due to an increase of interest in laser technology and natural phenomena in
the ionosphere, solar corona and planetary atmospheres. Most attention has been paid to
measurements of cross sections [2, 3] for charge transfer excitation but recently emphasis
was placed on determination of vibrational state distribution of excited electronic states
of CO + 2 ions. Experimental vibrational state distributions were compared with those
predicted by theory, especially Franck-Condon and curve-crossing models [4].
In the present work, collision-induced charge transfer experiments for N+( 4 S) + CO 2
were performed in a beam-gas arrangement under single-collision conditions. A detailed
description of the experimental setup has been given elsewhere [5]. Briefly, a beam of
mass-selected nitrogen ions collides with target gas. Luminescence is detected with optical
system consisting of optical spectrometer with a photon counting system. The collision
energies were in the 6-1000 eV lab range, target gas pressure was 15 mTorr.
The A 2 Π u - X 2 Π g and B 2 Σ + u - X2 Π g of CO + 2 luminescence spectra were recorded and
excitation functions for the charge-transfer reactions have been obtained.
Acknowledgment
This work was supported by the UG Grant BW 5200-5-0303-7.
References
[1] J.J. Leventhal, The emission of light from excited products of charge exchange reactions,
Gas Phase Ion Chemistry, Vol. III, M.T. Bowers, Ed. (Academic Press: Orlando, (1984))
[2] B.G. Lindsay, W.S. Yu, R.F. Stebbings, Physical Review A 71, 032705 (2005)
[3] J.B. Greenwood, A. Chutjian, S.J. Smith, The Astrophys. J. 529, 605-609 (2000)
[4] C. Poon, P.M. Mayer, J. Am. Soc. Mass Spectrom. 19, 1551-1558 (2008)
[5] A. Ehbrecht, A. Kowalski, Ch. Ottinger, Chem. Phys. Lett. 284, 205 (1998)
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