Wave in phonon as "forward and backward" movement vs temperature

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Discussion Overview

The discussion revolves around the interaction of light with molecules, specifically in the context of vibrating light harvesting antennas in biochemistry. Participants explore the implications of classical and quantum mechanical models on the behavior of electrons within molecules, particularly regarding temperature effects and wave-like properties.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant proposes that the rapid "for- and backward" movement of electrons in a molecule, influenced by light, could be modeled as a wave (phonon) and may affect temperature-related chaotic movements.
  • Another participant challenges the application of classical models to molecular behavior, emphasizing the quantum mechanical nature of electrons.
  • A follow-up response suggests that while classical models can be useful, they are based on abstractions and may not accurately represent the quantum behavior of electrons in molecules.
  • One participant expresses curiosity about the limitations of classical and quantum models, questioning whether nature might exhibit behaviors that are not captured by current theoretical frameworks, such as transitions between Fermi-Dirac and Bose-Einstein distributions.
  • The idea is raised that certain processes might remain hidden due to the constraints imposed by the Pauli exclusion principle, suggesting a potential gap in understanding molecular behavior at low temperatures.

Areas of Agreement / Disagreement

Participants express differing views on the applicability of classical versus quantum models to molecular behavior. There is no consensus on the validity of the proposed ideas, and the discussion remains unresolved regarding the implications of these models.

Contextual Notes

Participants acknowledge the limitations of classical models when applied to quantum systems, particularly in complex scenarios involving temperature and molecular vibrations. The discussion highlights the challenges in reconciling classical and quantum perspectives without resolving the underlying assumptions.

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TL;DR
How can we understand chaotic movement and temperature in a phonon? How is it affected by the waves of the phonon?
My first question here, so maybe not adequate or in the wrong topic, excuse me. I try to understand vibrating light harvesting antenna in biochemistry but it is a question of physics. We talk about a molecule with an emission spectra peak of about 650 nm.

In classical physics electrostatic and electrodynamic forces would let the electrons of a given molecule interact with each other in a rapid "for- and backward" movement in that molecule. That movement of the molecule may be more difficult to describe, but for the sake of discussion we stay with a likely constant linear extension and contraction of a chain like molecule, agitated by light. Because of the three (and more) body problem we are not able to predict those movements of the electrons, we just know that there is interaction, because of repulsion and the electric and magnetic fields created by the moving and spinning charges.

Now imagine the molecule as a wave (phonon). Isn't its rapid movement agitated by light influencing the chaotic movement of temperature and the electrons? The movements of the electrons could be seen as waves which interfere and resonate with the basic frequency of the phonon (molecule) and its multiples as in the Kuramoto model, couldn't it? So they would constantly get slightly redirected depending on their actual interfering or resonating waveform. Therefore couldn't it change the Boltzmann factor which depends on the temperature (as a measure for a probability distribution)?

Thank You
 
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This appears to be an attempt to apply classical models to a molecule, which is inherently quantum mechanical.
 
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Thanks for your statement. Can you please give me a hint on what is wrong. It is just an attempt to think in two different concepts parallel. I didn't want to mix them. Chemistry is full of cases of classic models applied to a molecule, since computing power is still limited and costly, isn't it?
 
Indeed, there are many things about molecules that can be modeled reasonably using a classical approach. But those models are usually based on abstractions, the most common being a molecular bond represented as a spring. The electrons in a molecule are very quantum mechanical, so you cannot consider a classical model for a molecule where electrons are still present.
 
Thank you for your explanation. I see your point and I agree with you. Let me please try to explain my thought in a different way: There are different theories/concepts with different abilities and limits. Classical physics work well for observable objects which are not very small. Quantum mechanics work very well for very small objects, but it is not easy to use them for complex molecules and varying temperature and vibration states, because the distribution is a basic assumption and the temperature an important component of the Boltzmann factor. I wonder if nature is able to fulfill conditions which we don't consider, because we exclude them by the decision we make, when we choose our concept. The Kuramoto model could be a hint to that. What if nature knew processes which change from Fermi Dirac distribution to Bose Einstein distribution (maybe just for one atom) by altering "temperature" close to zero by superposition of waves (Kuramoto model)? Would we be able to describe that quantum mechanically? Certainly chemists would never consider an atom behave like a boson because of the Pauli exclusion principle. Therefor it would stay hidden. But nevertheless it is thinkable, isn't it?
Gratefully C
 

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