Question about photoelectric effect?

AI Thread Summary
Electrons absorb photons only if the photon energy matches the energy levels in an atom, and if the photon energy exceeds the energy required to escape the atom, the excess energy converts to kinetic energy. The photoelectric effect demonstrates that the energy of emitted photoelectrons is proportional to the frequency of the incident light, with a minimum energy threshold known as the work function necessary for electron emission. This work function can be expressed in terms of frequency, and the relationship is defined by the equation h.frequency = k.E(max) + W. The discussion also highlights that photoelectric effects can occur at the atomic level, particularly in photoactive surfaces, where the interaction of photons with bound electrons leads to the emission of photoelectrons. Additionally, techniques like photoelectron spectroscopy utilize high-energy photon sources to investigate atomic structures and mechanisms involved in electron emission.
Clara Chung
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I think that an electron only absorb a photon with energy corresponding to the energy levels in an atom.

If the energy of a photon is higher than the energy between a specific energy level and infinity level (0 eV), it can also absorb the photon and the remained energy is changed to KE.
Am I right?
 
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Clara Chung said:
I think that an electron only absorb a photon with energy corresponding to the energy levels in an atom.

If the energy of a photon is higher than the energy between a specific energy level and infinity level (0 eV), it can also absorb the photon and the remained energy is changed to KE.
Let us examin/revisit the event of photo-emission...

The energy of emitted photo electrons is directly proportional to the frequency of incident light.It has also been observed that there must be a minimum energy needed for electrons to

escape from a particular metal surface and is called work function 'W' for that

metal.


The work function can be expressed in terms of frequency as, W= h. frequency(0)

the Photoelectric effect obey the equation,

h.frequency of incident light = k.E. (max) + W
on the above backdrop how you place your argument?
 
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drvrm said:
Let us examin/revisit the event of photo-emission...

The energy of emitted photo electrons is directly proportional to the frequency of incident light.It has also been observed that there must be a minimum energy needed for electrons to

escape from a particular metal surface and is called work function 'W' for that

metal.


The work function can be expressed in terms of frequency as, W= h. frequency(0)

the Photoelectric effect obey the equation,

h.frequency of incident light = k.E. (max) + W
on the above backdrop how you place your argument?

Work function is for a metal solid, can't photoelectric effect occur on an atom scale?
 
Clara Chung said:
Work function is for a metal solid, can't photoelectric effect occur on an atom scale?

When one is devising experiments of getting photo electrons from atoms of a particular kind...the atoms are in the form of a 'material' or layer of those atoms called 'Photo active surface/coatings'-

the name photo electrons is derived by the mechanism of energy transfer from a photon quantum to a bound electron in the atom of the active material ;
so basically its atomic absorption of photons - the work function has to be there as one is not having scattering of photon with a free atom ....
the array of atoms are also bound in a structure with surface interaction potentials and the ejected electron has to cross it to be registered as a photo current.

Moreover if one looks at Photo electron spectroscopy with variety of photon sources of higher energies
like UV or X-ray sources the spectroscopy helps to unravel the atomic structure.

There may be also "internal conversion" of emitted photons of an atom giving rise to photo electrons called "Auger electrons" but in each case the energy conservation has to be accounted for .
For more details about the the spectroscopy and variety of mechanisms one can look up the wiki or XAS(X-ray photoelectrons ) sites
Such as
<https://en.wikipedia.org/wiki/Photoelectric_effect#Three-step_model> and some more...
 
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