What is the unit for measuring crystal field stabilisation energy? In books it is mentioned Dq. What this Dq stands for? In some books cm-1 is also given. what does this signifies?

Hi

Dq is a measuring unit where 10 Dq is considered as the difference in energy between the orbitals having highest and lowest energy. When it is given in cm(-1), this signifies the wave number of the light having the energy that is needed. so both of them can be considered as the unit but Dq is used more often.