what is exchange energy and reorgnisation energy???

1. Electrons can change their shells i.e. electrons can move back and forth between energy levels or energy shells. Electrons can change their shells when they absorb or lose energy; however the energy loss or absorbed must be equal to the difference in potential energy between the two shells. When an electron loses energy, that energy is lost and released into the environment. The energy that is associated with the changing the shells by electrons is referred to as exchange energy.

2. Reorganization energy refers to the energy that is employed for the rearrangement of the electrons in an atom. Rearrangement is done in order to achieve stable half filled electronic configuration.