Author Topic: Peak shift and WS shape  (Read 59 times)

Rom

  • Professor
  • ****
  • Posts: 33
Peak shift and WS shape
« on: January 13, 2022, 08:27:00 PM »
Hi, could you explain, if WS shape and peak position depends of sample nature, why crystal type highly affects on them (WS shape, peak position shift)?
Thank you.

Probeman

  • Emeritus
  • *****
  • Posts: 2256
  • Never sleeps...
    • John Donovan
Re: Peak shift and WS shape
« Reply #1 on: January 14, 2022, 09:41:34 AM »
The terms you are looking for are Bragg's Law, polygonization and Rowland circle.

If I were you I would begin by cracking open some references. The general references in this post should be helpful:

https://probesoftware.com/smf/index.php?topic=343.msg1794#msg1794
The only stupid question is the one not asked!

Rom

  • Professor
  • ****
  • Posts: 33
Re: Peak shift and WS shape
« Reply #2 on: January 16, 2022, 08:09:58 PM »
I try to read more or less constantly  :).
It means peak shift and peak form nature depends of substance but possibility of seen these effects depends of spectral or energy resolution our equipment (crystal type and EPMA machine configuration).
Am I right?
« Last Edit: January 16, 2022, 08:14:59 PM by Rom »

Probeman

  • Emeritus
  • *****
  • Posts: 2256
  • Never sleeps...
    • John Donovan
Re: Peak shift and WS shape
« Reply #3 on: January 17, 2022, 09:39:34 AM »
I try to read more or less constantly  :).
It means peak shift and peak form nature depends of substance but possibility of seen these effects depends of spectral or energy resolution our equipment (crystal type and EPMA machine configuration).
Am I right?

The observed peak shift depends primarily on the chemical bond (e.g., oxide, carbide, boride, etc.), and secondarily on the valence and/or coordination. These papers should be read carefully:

G. F. Bastin and H. J. M. Heijligers, "Quantitative Electron Probe Microanalysis of Carbon in Binary Carbides," Parts I
and II, X-Ray Spectr. 15: 135-150, 1986

Bastin, G.F. and Heijligers, H.J.M (1991) Quantitative electron probe microanalysis of ultra-light elements (boron -
oxygen), in Electron Probe Quantitation, ed. K.F.J. Heinrich and D.E. Newbury, Plenum Press, NY, 145-161

Bastin, G.F. and Heijligers, H.J.M. (1992) Present and future of light element analysis with electron beam instruments,
Microbeam Analysis, 1, 61-73.

Armstrong, J.T. (1988) Accurate quantitative analysis of oxygen and nitrogen with a W/Si multi-layer crystal, in D.E.
Newbury, ed., Microbeam Analysis, p. 301-304

Here's a topic that discusses the application of Bastin's area peak factors:

https://probesoftware.com/smf/index.php?topic=536.0
The only stupid question is the one not asked!