Reaction Complexes

CHM 3000

Dissociative Mechanism

An intermediate w/ a reduce or lower coordination no.

Associative Mechanism

It has an intermediate w/ a higher coordination number.

Ligand Substitution

A reaction in which one Lewis base displaces another Lewis base from a Lewis acid

Interchange Mechanism

It has a transition state NOT an intermediate.

The exchange of the leaving group (X) and the incoming group (Y) happens at the same time.

MLnX ——> Mln+X

MLn + Y ——> MLnY

Dissociative Mechanism

MLnX + Y ——> MLnXY

MLnXY ——> MLnY + X

Associative Mechanism

MlnX + Y ——→ X —— MLn ——- Y ——→ MLnY + X

Interchange Mechanism

Thermodynamic Stability

The breakage and formation of bonds of the metal-ligand till equilibrium is reached.

Kinetic Stability

The speed at which the transformation will occur in order for the system to reach equilibrium

Liable complexes

The complexes where ligand are rapidly replaced by others

Inert complexes

The complexes where ligand are slowly replaced with others

Chelate effect and its relation to ligand denticity

The higher the denticity of the ligand, the higher its chelate effect.

Electronic Effect and its effect on the stability of the metal complexes

Complexes with the chelating ligands that have delocalized electron structures are stabilized by electronic effect 

The Irving William Series

The relative stability of complexes formed by divalent (bidentate)transition metals are affected by CFSE and electronic effect