An approximation used in quantum mechanics when the time dependence of parameters, such as the internuclear distance between atoms in a molecule, is slowly varying. This approximation means that the solution of the Schrödinger equation at one time goes continuously over to the solution at a later time. It was formulated by Max Born and the Soviet physicist Vladimir Alexandrovich Fock (1898–1974) in 1928. The Born-Oppenheimer approximation is an example of the adiabatic approximation.
Subjects: Chemistry — Physics.