Chemistry > Coordination Compounds > 12.0 Stability of Co-ordination compounds
Coordination Compounds
1.0 Basics
2.0 Addition Salt
3.0 Nomenclature of Co-ordination Compounds
4.0 Werner's Co-ordination Theory
5.0 Valence bond theory
6.0 Crystal field splitting theory (CFST)
7.0 Effective atomic number
8.0 Magnetic Moment
9.0 Application of Crystal Field Splitting Theory (CFST)
10.0 Isomerism in Co-ordination compounds
11.0 Organo-metallic compounds
12.0 Stability of Co-ordination compounds
12.1 Factors affecting stability of Co-ordination compounds
Nature of central metal atom:
- As size of the central metal atom decrease stability of the complexes increases .
- $M{n^{ + 2}} < F{e^{ + 2}} < C{o^{ + 2}} < N{i^{ + 2}} < C{u^{ + 2}} > Z{n^{ + 2}}$ This is called Irwin willion order.
- As the charge on the central metal atom increase, stability of the complexes increase .
Nature of ligand:
- As the size of the ligand decrease stability of the complex increase.
- As the basic character of the ligand increase stability of the complex of the complex increase.
- As the dipole moment of the neutral ligand increases, stability increase.
- The ligand which can form $\pi $ bonds can form stable complexes.
Example: $C{O^ - },C{N^ - },{R_3}P,{R_3}As$
Chelation: The polydentate ligand which can form ring structure with the central metal atom are called chelating ligands and the effect is called chelation.
- As the no of chelating ligand increase stability increase.
Example: en, gly, acac, EDTA
Macrocyclic effect: If the multi dentate ligand is cyclic and there is no consideration stearic effect then the complex is called Macrocyclic effect.
