Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-18T11:03:03.140Z Has data issue: false hasContentIssue false
  • English
  • Français

Analytical characteristics of a multilayer dispersion element (2d = 60 Å) in the determination of fluorine in minerals by electron microprobe

Published online by Cambridge University Press:  05 July 2018

Philip J. Potts  and
Andrew G. Tindle
Philip J. Potts
Affiliation:
Department of Earth Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
Andrew G. Tindle
Affiliation:
Department of Earth Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
Get access Rights & Permissions [Opens in a new window]

Abstract

The analytical characteristics of a W/Si multilayer dispersion element (MLDE) with a nominal 2d spacing of 60 Å are assessed and compared with those of a conventional thallium acid phthalate (TAP) crystal for the determination of fluorine in silicate and phosphate minerals by electron microprobe. Measured count rates for fluorine were found to be up to fourteen times higher using the MLDE compared with TAP giving improved detection limits of 0.02 to 0.08 wt. % F (six sigma, 100s count time) compared with equivalent data of 0.06 to 0.12 wt. % F by TAP. At equivalent spectrometer angles, peak widths by MLDE were broader by a factor of 2 to 3. However, an important advantage of MLDE was found to be the absence of multiple order diffractions higher than the second order. In consequence, the troublesome third order P-Kα line interference on the F-Kα line, normally encountered in the analysis of apatites, is absent in determinations made using the MLDE. Conversely small interferences on the F-Kα line were detected from the first-order Lα line of Fe and second-order Lα line of Mg. X-ray data and spectra of selected minerals are presented to demonstrate these interferences. Detection limits for elements that can also be determined using the MLDE were 0.07 to 0.15 wt. % oxygen and 0.34 wt. % carbon.

Keywords

electron microprobe analysisfluorinemultilayer dispersion element
Type
Experimental Studies
Information
Mineralogical Magazine , Volume 53 , Issue 371 , June 1989 , pp. 357 - 362
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1989

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Anzelmo, J. A., and Boyer, B. W. (1987) The analysis of carbon and other light elements using layered synthetic microstructures. Advances in X-ray Analysis, 30, 193-200.CrossRefGoogle Scholar
Arai, T. (1987) Measurements of soft and ultrasoft Xrays with total reflection monochromator. Ibid. 30, 213-23.Google Scholar
Barbee, T., Bleu, D. J., yon Rosenstiel, A. P., Knippenberg, W., Huizing, A., and Willich, P. (1987) LSM X-ray reflection crystals for light element analysis in electron microprobes. In 11th International Congress on X-ray Optics and Microanalysis (Brown, J. D., and Packwood, R. H., eds.), 520-2.Google Scholar
Bastin, G. F., and Heijligers, H. J. M. (1987) Recent developments in EPMA of very light elements. Ibid., 257-61.Google Scholar
Gilfrich, J. V. (1986) Multilayered structures as dispersing devices in X-ray spectrometry. Anal. Chim. Acta, 188, 51-7.CrossRefGoogle Scholar
Nicolosi, J. A., Groven, J. P., Merlo, D., and Jenkins, R. (1986) Layered synthetic microstructures for long wavelength X-ray spectrometry. Opt. Eng. 25, 964-9.Google Scholar
Nicolosi, J. A., Groven, J. P., Merlo, D., and Jenkins, R. (1987) The use of layered synthetic microstructures for quantitative analysis of elements: boron to magnesium. Advances in X-ray Analysis, 30, 183-92.CrossRefGoogle Scholar
Potts, P. J. (1987) A Handbook of silicate rock analysis. Blackie (Glasgow), 15–18.CrossRefGoogle Scholar
Potts, P. J., Tindle, A. G., and Isaacs, M. C. (1983). On the precision of electron microprobe data: a new test for the homogeneity of mineral standards. Am. Mineral. 68, 123742.Google Scholar
Scott, V. D., and Love, G. (1987) Correction procedures for quantitative electron probe microanalysis. In 11th International Congress on X-ray Optics and Microanalysis (Brown, J. D., and Packwood, R. H., eds.), 228-37.Google Scholar
van Eenbergen, A., and Volbert, B. (1987) Layered synthetic microstructures in sequential and simultaneous X-ray spectrometry. Advances in X-ray Analysis, 30, 201-11.CrossRefGoogle Scholar
White, E. W., and Johnson, G. G. (1970) X-ray emission and absorption wavelengths and two theta tables. Am. Soc. Testing Materials (Philadelphia), 293 pp.CrossRefGoogle Scholar