bond-dissociation energy (BDE)

For a diatomic molecule, the maximum vibrational energy that a molecule can have prior to its decomposition into the ground electronic states of the constituent atoms (spectroscopic bond-dissociation energy, ). The value is related to the chemical dissociation energy: , where is zero-point vibrational energy. This definition is usually extended to the dissociation of polyatomic molecules into certain molecular fragments through homolytic or heterolytic bond cleavages.