what is step wise stability constant and overall stability constant ? how are these two constants related ?

The formation of a complex proceeds by the stepwise addition of ligand to the metal.A number of successive equilibria can be formulated as follows:

Here, N is the maximum coordination number of the metal.

K₁, K₂ ……K_N are stepwise stability constants.

The overall stability constant is the equilibrium for the total reaction which can be represented as follows:

Here K_t is the overall stability constant.

Relation between overall stability constant and stepwise stability constant:

K_t = K₁ x K₂ x K₃ x ……..K_N