Discussion Overview
The discussion centers on the origin and justification of the 12th power dependency of Pauli repulsion within the context of the Lennard-Jones potential, comparing it to the 6th power dependency of dipole-dipole interactions. Participants explore the theoretical basis for this dependency and its implications for modeling intermolecular forces.
Discussion Character
- Exploratory, Technical explanation, Debate/contested
Main Points Raised
- One participant notes understanding the derivation of the 6th power dependency of dipole-dipole interactions but questions the lack of theoretical justification for the 12th power dependency of Pauli repulsion, suggesting it approximates repulsion due to overlapping electron orbitals.
- Another participant asserts that the 12th power dependence has no physical justification and that any high power or exponential dependence could suffice, emphasizing the mathematical convenience of choosing the repulsive term as the square of the attractive term.
- A different participant raises concerns about the significance of the relative values of Pauli repulsion and dipole-dipole attraction, questioning the rationale behind selecting "any high power or exponential dependence."
- It is mentioned that Pauli repulsion dominates at small distances, while dipole-dipole attraction prevails at larger distances, with a small region where both potentials are comparable, which can be adjusted by free parameters.
Areas of Agreement / Disagreement
Participants express differing views on the justification for the 12th power dependency, with some arguing it lacks physical basis while others question the implications of this choice. The discussion remains unresolved regarding the appropriateness of the power dependency used in the Lennard-Jones potential.
Contextual Notes
Participants highlight the mathematical convenience of the chosen dependencies and the significance of the parameters that define the balance between repulsion and attraction, but do not resolve the underlying theoretical justifications or implications.