As suggested in class, one can model two adjacent inert gas atoms as linear oscillating electric dipoles. Fill in the mathematics between the following two equations:
e^2 / (4πε₀) * (1 / (R + R_x)^2)
and
2^2 * x^2 ~ (e^2 / (4πε₀)) * (1 / R^3)
(b) As suggested in the lecture, a normal mode transformation can change the coupled oscillating dipole problem into a sum of two independent oscillators with slightly modified energies and spring constants. Do the math which uses the normal mode approximation to go from the coupled oscillator Hamiltonian:
p₠* Cx₠+ p₂ * Cx₂ + (2e^2 * x₠* x₂) / (4πε₀ * R^3)
to two uncoupled oscillators:
pâ‚ * Câ‚ + pâ‚‚ * Câ‚‚ + (2e^2 * xâ‚^2) / (4πε₀ * R^3) + (2e^2 * xâ‚‚^2) / (4πε₀ * R^3)
(c) In the lecture, we argued that the coupling lowers the ground state energy of the two oscillator system as follows:
hwo = (2e^2 * R^6) / (8πε₀ * R^3)
A R^6
tw + hwa = hwo
two
Prove this statement.