dissociation energy $$E_{\text{d}}$$, $$D$$

https://doi.org/10.1351/goldbook.D01802
Energy required to dissociate a molecule into two parts. Subscripts 0 and e, i.e. $$D_{0}$$ and $$D_{\text{e}}$$, are used to denote the dissociation from the ground state and potential energy minimum, respectively.