Bohr-Sommerfeld type

This clearly was, at least, a very uncomfortable situation and Sidgwick attempted to avoid the difficulty by shifting the argument away from atomic structure as such, to the idea of molecular structure in which pairs of electrons had common orbits of the Bohr-Sommerfeld type involving the molecular nuclei. He... 

In this section, we intend to show that for a certain type of models the above imposed restrictions become the ordinary well-known Bohr-Sommerfeld quantization conditions [82]. For this purpose, we consider the following non-adiabatic coupling matrix x ... 

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