Resonant swing spring

A. Three-Dimensional Quantum Monodromy of the Resonant Swing Spring... 

The next account starts by summarizing the three-dimensional monodromy of the resonant swing spring. It is then shown how the geometrical arguments of Section IV may be applied to examining the nature of the two-dimensional monodromy within a given polyad. 

Analysis of the prototypical resonant swing spring model [11-13] shows that Fermi resonance with conserved angular momentum is an intrinsically three-dimensional phenomenon. The form of the 3x3 monodromy matrix was given. 

Bonds stretch, bend, and wag as if they were balls attached by springs. A light wave of the correct frequency will be in resonance with a bond motion and transfer its energy to this motion, like the parent pushing the swinging child. We say the light is absorbed by the molecule. 

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