Spectroscopy from a classical light wave or photon only? In chemistry we mostly regard light/electromagnetic radiation as a beam of particles or photons. This is a very useful model to explain molecular excitations and ionisations from quantum interactions. However, I am wondering how far the electromagnetism model of light as a propagating disturbance will get us?  
My university friend who studies physics assures me that Maxwell's laws are among some of the most beautiful in all of physics. To this end I am excited to find areas where we can share this view. But most of my degree focuses on light-matter interactions from the photon model only e.g scattering techniques. 
In particular imagine some spectroscopy technique,


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*My approach would be to describe a light scattering model from the collision of incident photons with electrons, energy exchange and promotion or relaxation to a virtual state and photon emission.

*The alternative is an electromagnetic field that encounters static charges and superposes into a resultant field.


I am not familiar with this second approach and was hoping for a little introduction to the classical model applied to the spectroscopy of solids/molecules etc. Thank you for your time.
 A: How much of physics can be explained by quantum mechanics alone.
99% of what is explained on PSE with QM is about the double-slit experiments and the interaction of atoms, subatomic and elementary particles.  The latter starts from the equations of the spectra of EM radiation (Balmer, ...) and Planck blackbody radiation and infers the distribution of electrons around the nucleus.
Where we are.
The slit experiments show a distribution pattern on the screen with a periodic intensity described by a wave equation. Everything else is interpretation, because we have no instrument for a direct measurement that does not affect the propagation path. In addition, the spherical wave (Huygens' principle) behind an obstacle does not exist. The deflection of particles behind a single slit is blanked out to the left and right of the slit, while in the case of water waves it propagates through all 180° behind the slit.
Bor's premise about orbits was wrong and the application of spectral line distribution (especially or even exclusively of hydrogen) to atomic structure is not in agreement with the periodic table of elements. We still apply the Balmer and Rydberg formulas of the emission lines of hydrogen to the electron distribution for all elements. There is a clear periodicity of chemical behavior for 2, 8, 8, 18, and 18 elements and QM needs a lot of additional rules to agree with the PTE.
Some suggestions.
The magnetic dipole of the electron plays the main rule in electron distribution in atoms. Chemist Gilbert N. Lewis' cubic model for the second and third periods and Paulis' principle are a good place to start. At four edges of the cube the magnetic dipoles are directed inward (spin down) and at the other edges outward. Perfect symmetry.
The electron is not only equally equipped with a magnetic and an electric field. However, the electric field is partially stripped off as it approaches the nucleus. The emitted photons arise from the energy of the electric field of the electron and the corresponding protons.  The discreteness of the photon emission indicates the possibility that the emission is stopped near the nucleus. There is no longer an energy packet in the electric field of the electron-proton system sufficient for photon emission. This would explain the stability of the atoms.
Last but not least, particle passage through slits for photons and the subatomic particles should be investigated in different materials and at applied electric potential or a magnetic field. The observation of a quantized interaction between the surface electrons of the slit and the passing particles would put an end to the agonizing discussion about the spooky behavior in inference experiments. Incidentally, while interference does indeed occur in water waves, such an explanation for photons is untenable today. Light in the low intensity range does not interact.
