Talk:Electron energy loss spectroscopy

Latest comment: 7 years ago by Magnunor in topic Imaging - news

Pennycook

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http://blogs.discovermagazine.com/intersection/2011/07/07/alleged-scientific-fraud-lawsuit-reveals-doe-failures/#.VCHNjPldV8E Please also google [Pennycook Misconduct]. All Pennycook publications should be removed from this wiki page.

The issue about Pennycook has been raised for more than 30 days. No one objects the removal of the corresponding references. All Pennycook publications were removed. — Preceding unsigned comment added by 69.120.21.76 (talk) 01:14, 6 December 2014 (UTC)Reply

EELS and EDX

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To illustrate a bit the differences between EELS and EDX it could be mentioned that EELS gets its information from forward- and unscattered electron whereas EDX only detects backscattered electrons. Since heavy atoms have a greater cross section this explains the different sensitivity of both methods and their complementary behaviour. --Mlohr (talk) 10:52, 12 June 2012 (UTC)Reply

This is not correct. EDX detects X-rays. Since the energy resolution of EDX detectors (not WDX) is about 200 times worse than the resolution of an EEL spectrometer, edges at small energies (few hundered eV) cannot be resolved. The cross section for an EEL event decreases with the loss energy such that at energies above about 2 keV no useful signal is available. That's why EDX can take over.

The Sensitivity of EELS is higher because an EELS-Detector will see almost all electrons that have passed the specimen owing to the high energy of the impinging electrons (about 80-300 kV in most modern TEMs) leading to pronounced forward scattering. On the other hand, EDX detectors cover only a very small fraction of the hemisphere therefor miss almost all X-rays emitted from the specimen. --Mwollgarten (talk) 14:48, 28 January 2014 (UTC)Reply

Thickness measurements

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A remark for the procedure: It's not necessary to extract the ZLP from the spectrum. One can also record the loss spectrum and a second one - a filtered image. For the filtered image a slit, typically in the range of 1-10 eV, is inserted in the spectrometer to filter the scattered electrons. Since both intensities are measured directly and without any algorythm trying to isolate the ZLP from the rest IMO this is the better method. This could be added to point 2 of the list. --Mlohr (talk) 11:34, 12 June 2012 (UTC)Reply

Imaging - news

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Is Electron Micrographs Get a Dash of Color worth mentioning here ? - Rod57 (talk) 21:59, 16 November 2016 (UTC)Reply

I think it fits well in here, since it shows an example of EELS used on a biological sample. Especially since, in my experience, people usually associate EELS with characterization of solid state samples. Magnunor (talk) 20:13, 5 December 2016 (UTC)Reply