Spin Evolution in the Born‐Oppenheimer Approximation

Abstract The first part of this article attempts to highlight in chronological order some prominent papers that have direct connexion with the Born‐Oppenheimer approximation. This timeline successively points role level crossing, notions gauge field and geometrical or Berry phase, early experiments were accounted for concept, its major understanding anomalous transport solids. second analyzes time evolution states under adiabatic approximation when are spin degenerate. phase thus found entails an electron evolution. Then, we examine case moleclar dynamics. Starting from approximation, obtain a by replacing classical nuclear positions their quantum mechanical counterparts terms describe electrostatic interactions between nuclei electrons.