|WikiProject Physics||(Rated Stub-class, Low-importance)|
Moved from article page
I moved the following text here from the article page. I don't think it is helpful as it is, but it might save as a basis for phrasing a more accessible example.
- In classical mechanics (CM), at the molecular level, one can define a potential energy surface. This is a purely classical construct and does not hold for QM. In QM an adiabatic state (i.e. not resonant with other states) will remain occupied. For example in a diatomic, the classical interpretation of the stretch mode is a periodic vibration. Here CM agrees with QM and the system is perfectly adiabatic (all the energy remains in the vib mode). On multidimensional surfaces one can imagine a surface where a trajectory (i.e. a marble rolling on a surface w/o angular momentum) might have an almost periodic motion but just does not come back to exactly the same phase space location (i.e. after one vibrational phase the geometry and momenta of the atoms of the molecule are very similar but not exactly the same).
- This is a “Vague tori” as I understand it from Hase JPC 2009 jp806659f
— HHHIPPO 21:16, 28 January 2013 (UTC)