Question

Explain the Crystal Field Theory (CFT) of coordination compounds.

Hint:

CFT helps explain magnetic properties, color, and stability of transition metal complexes.

Answer 1

Step 1: Introduction to CFT Crystal Field Theory (CFT) explains the splitting of d-orbitals in transition metal complexes due to ligand interaction. Step 2: Octahedral Splitting In an octahedral field, d-orbitals split into two energy levels: - \( t_{2g} \) (lower energy): \( d_{xy}, d_{yz}, d_{zx} \) - \( e_g \) (higher energy): \( d_{z^2}, d_{x^2-y^2} \) \[ \Delta_o = \text{energy gap between these levels} \] Step 3: High-Spin vs Low-Spin Complexes - Weak-field ligands (Cl\(^-\), H\(_2\)O) → High-spin, small \(\Delta_o\)
- Strong-field ligands (CN\(^-\), CO) → Low-spin, large \(\Delta_o\)