Evaluation of the use of Gaussian ϕ(ρz) curves in quantitative electron probe microanalysis: A new optimization

Abstract

A computer program based on the use of Gaussian expressions for the x‐ray distribution with depth [ϕ(ρz)curves] was tested on its usefulness for quantitative electron probe microanalysis. As the good results originally claimed for a similar program could not be reproduced initially, it was subjected to a detailed analysis. As a result, some modifications in the approach are proposed. Apart from increasing the speed of calculation considerably, the modified expressions provide a better insight into the delicate balance which has to exit between the relevant quantities involved. After a new optimization process the modified program was tested on about 450 published microanalyses. The results show that the ϕ(ρz) approach is indeed very promising as a narrow histogram with an r. m. s. value of 5. 4% could be produced. Finally, some suggestions are made for future improvements.

The solid state diffusion reaction of copper with germanium; a comparison between silicon and germanium

“…Quantitative analyses were carried out by use of electron probe micro analysis (EPMA). The pure element was used as calibration standard, as were a beam current of 10 nA, an accelerating voltage of 20 kV, and a BAS correction program [3]. Figure 1 shows the copper-germanium phase diagram according to Hansen [4] and Hultgren [5].…”

Eudialyte-group minerals from the Monte de Trigo alkaline suite, Brazil: composition and petrological implications

“…A combination of well-characterized natural and synthetic standards was used. The data were processed using the PROZA procedure (Bastin et al 1984). Special care was taken in the selection of the peak and background position to eliminate peak overlap.…”

A characteristic fluorescence correction factor for use in electron probe microanalysis. II. Evaluation of experimental results and comparisons

“…that of the modified Gaussian distribution. This description was first proposed by Packwood and Brown [38] and has been further elaborated by several authors [5,[39][40][41][42][43] :…”

“…Generally [5,[38][39][40][41] the expression of Love et al [44] is used for the quantification of this parameter; some recent models, though, employ new quantifications [26,42], since the formula given by Love et aL [44] Figure 3 shows the percental deviations of the absorption terms of Wittry [46], Reed [1] (taken from Castaing [33]), Criss [47] and Heinrich [8], respectively, from those calculated in the present paper for a K~K excitation. The exciting element is nickel, and the excited elements have atomic numbers ranging from Z = 18 to Z = 26.…”

“…-), and the presented model (-). distribution models, viz., that of Packwood and Brown [38], that of Bastin et al published in 1984 [39,40], that of Bastin et al published two years later [41]; that of Bastin and Heijligers [5], and finally that of Rehbach and Karduck [42].…”