Can Electrons Absorb Photons With Different Energy Levels?

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In summary: One speaks of absorption lines, but really the situation is more complicated.In summary, the amount of energy needed for an electron to absorb a photon in an atom does not have to be exactly equal to the energy difference between the two energy levels. This is due to broadening of spectral lines, which can come from natural linewidth, doppler broadening, and collisional broadening. Therefore, an atom can absorb photons from different sources, not just ones with matching energies. This is also why you can observe discrete absorption lines in the solar spectrum, even though the sun's radiation is continuous.
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MHD93
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For electrons in some atom to absorb a photon having some amount of energy, must this energy be (exactly) equal to the difference between the two energy levels?, can't it be absorbed when its energy is more than that difference?

Because in the case of (exact-equality), it would be hard for an electron in a hydrogen atom to absorb photons emitted by different atoms, since the differences of their energy levels can hardly (or even impossibly) match that of hydrogen's.

Consequently, hydrogen receives only from hydrogen..?!

ThanQ U
 
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Short answer: No

Actually, the energy does not have to match exactly. One speaks of broadening of spectral lines, meaning that there is a finite range of frequencies that "match". Broadening comes from several sources.

First of all, there is natural linewidth: Since the excited atomic state has a finite lifetime, the energies do not have to match exactly (roughly speaking, there is a Heisenberg uncertainty principle trading off energy against time, although this explanation is a bit simplistic).
You also have doppler broadening: Because of the Doppler effect, the exact frequency matching your atomic transition depends on the relative motion between the atom and the light source. Finally you have collisional broadening coming from the scattering between atoms.
http://en.wikipedia.org/wiki/Spectral_line" has a short explanation of this as well, however with poor references. Textbooks on quantum optics (like Loudon's classic "The quantum theory of light) explains this on an advanced level.
 
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Consequently, hydrogen receives only from hydrogen..?!
What typically excites an atom is black body radiation, which has a continuous spectrum. Thus you observe discrete absorption lines in the solar specturm.
 

FAQ: Can Electrons Absorb Photons With Different Energy Levels?

What are electrons and photons?

Electrons are subatomic particles that carry a negative charge and are found in the nucleus of an atom. Photons are packets of energy that make up electromagnetic radiation, including light.

How do electrons absorb photons with different energy levels?

When an electron absorbs a photon, it gains energy and moves to a higher energy level. The energy of the photon must match the difference in energy between the electron's initial and final energy levels.

Can electrons absorb photons with any energy level?

No, electrons can only absorb photons with energy levels that correspond to the difference in energy between their energy levels. If the photon has too much or too little energy, it will not be absorbed by the electron.

What happens to the absorbed energy?

After absorbing a photon, the electron will move to a higher energy level. This energy can then be released as the electron moves back to its original energy level, emitting a photon with the same energy level as the absorbed one.

What applications does this phenomenon have?

The ability of electrons to absorb photons with different energy levels is essential in many fields, including solar cells, photosynthesis, and spectroscopy. It also plays a crucial role in electronic devices such as LEDs and lasers.

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