It can be contrasted with a method that uses the extended Lagrangian approach and is named for Car and Parrinello.
The desire to introduce it to the path integral expression for the canonical partition function led Cao and Berne to devise a free energy version of it. It can be contrasted with a method that uses the extended Lagrangian approach and is named for Car and Parrinello. An extension of it to transitions between electronic energy levels leads to the Franck-Condon principle. It neglects vibronic coupling, one form of which is the Renner- Teller effect, and it often breaks down in diatomic molecules. Derived by using the Eckart conditions, it is used to alleviate the task of computing a molecule's energy and wave-function, and it divides the latter into electronic and nuclear components because of the large nuclear mass. For 10 points, name this doubly-eponymous approximation.
The desire to introduce it to the path integral expression for the canonical partition function led Cao and Berne to devise a free energy version of it.
{Born-Oppenheimer} approximation