Question

Explain Homoleptic and Heteroleptic complexes with example.

Hint:

Prefix "Homo-" means same, and "Hetero-" means different. This applies to the nature of the ligands surrounding the metal.

Answer 1

Step 1: Understanding the Concept:
Coordination complexes consist of a central metal ion bonded to surrounding molecules or ions called ligands. The classification depends on the variety of ligands present.
Step 3: Detailed Explanation:
1. Homoleptic Complexes:
These are complexes in which the central metal atom or ion is coordinated to only one kind of donor group (ligand).
Example: \([Co(NH_3)_6]^{3+}\) (Hexaamminecobalt(III) ion). Here, all six ligands are ammonia molecules.
2. Heteroleptic Complexes:
These are complexes in which the central metal atom or ion is coordinated to more than one kind of donor group (ligand).
Example: \([Co(NH_3)_4Cl_2]^+\) (Tetraamminedichloridocobalt(III) ion). Here, two types of ligands are present: four ammonia molecules and two chloride ions.
Step 4: Final Answer: Homoleptic complexes have uniform ligands (e.g., \([Ni(CO)_4]\)), whereas heteroleptic complexes have varied ligands (e.g., \([Pt(NH_3)_2Cl_2]\)).