Why Can't XRF & LIBS Distinguish Element Valences?

  • Thread starter xhtp2000
  • Start date
  • Tags
    Element
In summary, the conversation discusses the limitations of XRF and LIBS in distinguishing different valences of an element. The wavelength of fluorescence emission is dependent on the difference between the core and outer energy state, but the resolution of the detector may not be able to detect the slim difference between valences. The second question considers whether the excited electrons in LIBS can be described as a Bosse-Einstein state and if the difference in valence states can be detected using a high resolution spectrograph.
  • #1
xhtp2000
21
0
Sorry, I had the typo in the topic, it should be"Why can't XRF and LIBS distinguish different valences of a certain element?"

Dear all, I have two questions for you:

1: As in known, in the case for transition and rare Earth elements, different valences lead to totally different properties. It is said that XRF can only detect the concentration of a certain element, but can not distinguish the valences of this element. Is there anyone who can tell me why? Because the wavelength of the fluorescence emission depends on the difference between the core and outer energy state and in different combined state i.e. different valences of the element, this difference between the core and outer energy state should also be different. Is that because the resolution of detector can not tell this slim difference?
2: In the case of laser-induced breakdown spectroscopy, the electrons are excited to quasi-free electrons due to the ionization during that breakdown process, can this state of electrons be described as sth. similar to Bosse-Einstein state as for photons? The excited electrons will come back to the valence state afterwards, this valence state should be different in different combined state? If yes, then the wavelength of emission should also be different, and if this difference detectable using high resolution spectrograph?

Thanks so much!
 
Last edited:
Physics news on Phys.org
  • #2


What do you mean by "distinguish the valences"?
 

1. Why can't XRF and LIBS distinguish element valences?

XRF (X-ray fluorescence) and LIBS (laser-induced breakdown spectroscopy) are both spectroscopic techniques that are used to identify and quantify the elements present in a sample. However, they are not able to distinguish between different valence states of the same element. This is because these techniques rely on the measurement of the energy levels of electrons, and valence states do not significantly affect these energy levels.

2. Can XRF and LIBS be used to determine the oxidation state of an element?

No, XRF and LIBS cannot be used to determine the oxidation state of an element. These techniques can only provide information about the elemental composition of a sample, not the chemical or electronic state of the elements.

3. Are there any other methods that can be used to distinguish element valences?

Yes, there are other techniques that can be used to distinguish element valences, such as X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). These techniques rely on the measurement of the energy levels of electrons that are specific to a particular valence state.

4. Can XRF and LIBS provide any information about the chemical bonding in a sample?

No, XRF and LIBS do not provide any information about the chemical bonding in a sample. These techniques only measure the elemental composition of a sample, not the chemical or molecular structure.

5. Is it important to know the valence states of elements in a sample?

Yes, it can be important to know the valence states of elements in a sample, especially in cases where the electronic structure of an element is related to its chemical reactivity or properties. However, XRF and LIBS can still provide valuable information about the elemental composition of a sample, which can be useful in many applications.

Similar threads

  • Other Physics Topics
Replies
16
Views
4K
  • Atomic and Condensed Matter
Replies
1
Views
2K
Replies
3
Views
3K
  • Atomic and Condensed Matter
Replies
5
Views
3K
Replies
4
Views
10K
Replies
3
Views
3K
Replies
7
Views
1K
  • Other Physics Topics
Replies
0
Views
725
Replies
8
Views
2K
  • Atomic and Condensed Matter
Replies
4
Views
2K
Back
Top