Born-Oppenheimer approximation

The Born-Oppenheimer approximation is a method used in quantum chemistry to simplify the analysis of molecules. It assumes that because nuclei are much heavier and move more slowly than electrons, their motions can be treated separately. This allows scientists to first calculate electronic behavior assuming fixed nuclei, and then analyze how the nuclei move based on that electronic structure. This separation makes complex calculations more manageable, providing a practical way to understand and predict molecular properties and reactions without losing essential details.