Emission Spectra: which electrons?

In summary, a newbie to a forum is impressed by the material and has been searching for an answer to a question posed by one of their students. They have not been able to find an answer in their own texts or online, and are wondering if spectra are generated by electrons other than valence electrons. Other forum members discuss the involvement of valence electrons and other electrons in the emission spectra of complex atoms, and the possibility of observing an absorption spectrum through photon excitation. The original poster thanks those who have considered their question and asks for any online references on this topic.
  • #1
Elly
2
0
I am a newbie to the forum and impressed by the breadth and depth of the material here. After searching I am unable to answer a question that I have been pondering.

One of my brightest students asked whether electrons other than the valence electrons were involved in the emission spectra of complex atoms.

Research in my own texts didn't reveal an answer, nor did research here or on the net. The closest I got suggests that spectra are usually but not always generated by transitions of the valence electrons.

http://www.daviddarling.info/encyclopedia/E/energy_level.html
http://www.800mainstreet.com/spect/spectrum.html

Can anyone confirm that spectra are generated by electrons other than the valence electrons? Any net references would also be appreciated.
 
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  • #2
Elly said:
I am a newbie to the forum and impressed by the breadth and depth of the material here. After searching I am unable to answer a question that I have been pondering.

One of my brightest students asked whether electrons other than the valence electrons were involved in the emission spectra of complex atoms.

Research in my own texts didn't reveal an answer, nor did research here or on the net. The closest I got suggests that spectra are usually but not always generated by transitions of the valence electrons.

http://www.daviddarling.info/encyclopedia/E/energy_level.html
http://www.800mainstreet.com/spect/spectrum.html

Can anyone confirm that spectra are generated by electrons other than the valence electrons? Any net references would also be appreciated.

Hello Elly, as far as I can recall valence electrons can cause lines in the infra red, visible and ultraviolet regions of the spectrum but in more energetic regions other electrons get involved.I am thinking in particular about the characteristic lines superimposed on the continuous spectrum from an X ray tube these lines being caused by electron transitions between shells.The Gamma spectrum from certain radioactive materials is caused by nucleon transitions within the nucleus.I am pretty rusty on this stuff and hopefully others will pop into inform us both.:smile:
 
  • #3
Hi, i am not exactly proficient in this area and i would greatly appreciate anyone that can correct me if my discussion is wrong so here's what i think.

I remembered that for electron(s) to be excited to another quantum level, the energy of the light ray/beam(seriously have no idea the difference between ray and beam hope someone can enlighten me :biggrin:) have to have the exact energy say between n quantum level and i quantum level? So that would mean that when an atom receives energy only electrons from n quantum level will be promoted to i quantum level and no other electrons from other levels will be excited correct? If that is the case can we conclude that excitation is not limited only to the valence electrons?
 
  • #4
semc said:
Hi, i am not exactly proficient in this area and i would greatly appreciate anyone that can correct me if my discussion is wrong so here's what i think.

I remembered that for electron(s) to be excited to another quantum level, the energy of the light ray/beam(seriously have no idea the difference between ray and beam hope someone can enlighten me :biggrin:) have to have the exact energy say between n quantum level and i quantum level? So that would mean that when an atom receives energy only electrons from n quantum level will be promoted to i quantum level and no other electrons from other levels will be excited correct? If that is the case can we conclude that excitation is not limited only to the valence electrons?

I think photons would be the most appropriate word to use in this context and what you have described here seems to make sense electrons other than valence electrons becoming involved particularly when we go into the higher frequency end of the spectrum.With photon excitation one might expect to be able to observe an absorption spectrum.
 
  • #5
Thank you Dadface. Your reply was much appreciated. And thanks to all who considered my question.

Does anyone have any online references they can point me to covering this area?
 

What is an emission spectrum?

An emission spectrum is a series of colored lines or bands of light emitted by a substance when it is energized. Each element produces a unique emission spectrum, allowing scientists to identify elements present in a substance.

What causes emission spectra?

Emission spectra are caused by the movement of electrons within an atom. When an atom is energized, its electrons jump to higher energy levels. As they return to their original energy levels, they release energy in the form of light, which creates the emission spectrum.

What is the difference between atomic and molecular emission spectra?

Atomic emission spectra are produced by individual atoms, while molecular emission spectra are produced by molecules. Molecular spectra are more complex and contain more lines due to the different ways that molecules can vibrate and rotate.

How are emission spectra used in science?

Emission spectra are used to identify elements present in a substance, as each element has a unique emission spectrum. They are also used to study the energy levels of atoms and molecules, and to determine the composition and properties of substances.

Can emission spectra be used to determine the temperature of a substance?

Yes, the intensity and width of emission lines in a spectrum can be used to calculate the temperature of the substance. This is known as spectroscopic temperature measurement, and it is commonly used in astronomy to study the temperature of stars and planets.

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