Implications of line number to line intensity logarithmic relationship for emission spectrochemical analysis

1986 ◽  
Vol 58 (4) ◽  
pp. 802-807 ◽  
Author(s):  
Alexander. Scheeline
1959 ◽  
Vol 3 ◽  
pp. 109-129
Author(s):  
William J. Campbell

AbstractLine intensity and background measurements were made on the K lines for the elements with atomic numbers 16 to 60, L lines for the elements above atomic number 42, and M lines for elements above atomic number 80. Three general classes of samples were investigated: (1) infinitely thick, (2) microgram deposits, and (3) thin layers.These studies show that longer-wavelength L radiation may be preferable to the K series lines from the same element in the range of elements with atomic numbers 42 to 60, In particular the Lα lines are more intense than the K series lines from Class 2 and 3 samples. With Class 1 samples the Lα lines are weaker than the K series but their line-to-background ratio is superior to the K series.M series lines show little promise for spectrochemical analysis except for elements with atomic numbers 90 to 92; for example, with uranium samples in Class 2 and 3, the very high line-to-background ratio of the UMβ1 line may have limited application.Elements with atomic numbers from 16 to 22 are more sensitive than expected due to the very high line-to-background ratios and the reduced collimation requirements in this longwavelength region.


1966 ◽  
Vol 24 ◽  
pp. 3-5
Author(s):  
W. W. Morgan

1. The definition of “normal” stars in spectral classification changes with time; at the time of the publication of theYerkes Spectral Atlasthe term “normal” was applied to stars whose spectra could be fitted smoothly into a two-dimensional array. Thus, at that time, weak-lined spectra (RR Lyrae and HD 140283) would have been considered peculiar. At the present time we would tend to classify such spectra as “normal”—in a more complicated classification scheme which would have a parameter varying with metallic-line intensity within a specific spectral subdivision.


Author(s):  
C. C. Ahn ◽  
D. H. Pearson ◽  
P. Rez ◽  
B. Fultz

Previous experimental measurements of the total white line intensities from L2,3 energy loss spectra of 3d transition metals reported a linear dependence of the white line intensity on 3d occupancy. These results are inconsistent, however, with behavior inferred from relativistic one electron Dirac-Fock calculations, which show an initial increase followed by a decrease of total white line intensity across the 3d series. This inconsistency with experimental data is especially puzzling in light of work by Thole, et al., which successfully calculates x-ray absorption spectra of the lanthanide M4,5 white lines by employing a less rigorous Hartree-Fock calculation with relativistic corrections based on the work of Cowan. When restricted to transitions allowed by dipole selection rules, the calculated spectra of the lanthanide M4,5 white lines show a decreasing intensity as a function of Z that was consistent with the available experimental data.Here we report the results of Dirac-Fock calculations of the L2,3 white lines of the 3d and 4d elements, and compare the results to the experimental work of Pearson et al. In a previous study, similar calculations helped to account for the non-statistical behavior of L3/L2 ratios of the 3d metals. We assumed that all metals had a single 4s electron. Because these calculations provide absolute transition probabilities, to compare the calculated white line intensities to the experimental data, we normalized the calculated intensities to the intensity of the continuum above the L3 edges. The continuum intensity was obtained by Hartree-Slater calculations, and the normalization factor for the white line intensities was the integrated intensity in an energy window of fixed width and position above the L3 edge of each element.


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