Effect of small quantities of oxygen in a neon glow discharge

Mushtaq, Sohail and Steers, Edward B. M. and Pickering, Juliet C. and Weinstein, Viktoria (2014) Effect of small quantities of oxygen in a neon glow discharge. J. Anal. At. Spectrom., 29 (11). pp. 2027-2041. ISSN 0267-9477

Full text not available from this repository. (Request a copy)
Official URL: http://dx.doi.org/10.1039/C4JA00192C

Abstract

Many studies have already been carried out on the effect of small quantities of molecular gases (oxygen, hydrogen and nitrogen) in argon analytical glow discharges (GD). We report here the first comprehensive study using small amounts of oxygen in a neon GD plasma with copper sample. Whilst neon is too costly for routine use in analytical GD spectrometry, such studies help the interpretation of the excitation and ionization processes taking place in the discharge. In all GD, Penning ionization (PI) of analyte atoms, asymmetric charge transfer (ACT) and Penning excitation (PE) of analyte ions have significant roles in populating excited ionized levels, so the higher energy of the neon metastable states and the higher ionization energy compared to argon have a major effect on the appearance of the copper spectrum. Examples of all these effects for copper ionic lines in neon–oxygen mixtures will be presented. For copper atomic lines, it is observed that the changes (such as enhancement due to change in self-absorption and three body collisional recombination or reduction where neutralization of copper ions is suppressed) in emission yield ratios are more significant when higher oxygen concentrations are used. A clear trend of cascading for neon ionic lines with excitation energies about ∼56 eV and ∼53 eV could be observed in neon–oxygen mixtures. Excitation of the higher atomic energy levels of copper and neon by neutralization of their ionic ground states is also discussed in this work.

Item Type: Article
Uncontrolled Keywords: glow discharge spectroscopy; neon glow discharge
Subjects: 500 Natural Sciences and Mathemetics > 540 Chemistry & allied sciences
Department: School of Human Sciences
Related URLs:
Depositing User: Bal Virdee
Date Deposited: 22 Oct 2015 17:52
Last Modified: 22 Oct 2015 17:52
URI: http://repository.londonmet.ac.uk/id/eprint/813

Actions (login required)

View Item View Item