Comparison of emission characteristics for lanthanide elements between in a glow discharge spectrometry and in an ICP spectrometry

In a Grimm-style glow discharge optical emission spectrometry, the emission characteristics of the spectral lines of all lanthanide elements, except for Pm, were investigated. The ionic resonance emission lines, which are commonly employed as analytical lines in TCP analysis, are also very intense in glow discharge emissions. In addition, atomic resonance lines having excitation energies of 2.5-3 eV can be predominantly excited by the glow discharge plasma, thus being available for the trace determination. These effects might be explained based on the difference in the excitation mechanisms between the glow discharge plasma and the ICP. The limit of determination obtained by glow discharge excitations, which was defined as the sample concentration corresponding to three-times the full fluctuation of the background intensities, was estimated to be 2.4 × 10^-4 atomic% for Eu I 459.402 nm, 1-6 × 10^-4 atomic% for Yb II 328.937 nm, and 6.1 × 10^-4 atomic% for Dy I 421.170 nm, for example.