Q23.86P - Chemistry: Molecular Nature Of Matter And Change

Question

What is the distinction between a weak-field ligand and a strong-field ligand? Give an example of each.

Step-by-Step Solution

Answer

Strong-field ligands give larger splitting energy $\left(∆\right)$ and weak-field ligands give smaller splitting energy $\left(∆\right)$. Example for strong-field ligand: CO Example for weak-field ligand: ${\mathrm{Cl}}^{-}$

Step 1: Definition of ligand

A ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex.

Step 2: Explanation

The main distinction between weak-field ligands and strong-field ligands is that the strong-field ligands give larger splitting energy $\left(∆\right)$ because they cause large splitting of d orbitals and the weak-field ligands give smaller splitting energy $\left(∆\right)$ because they don't cause large splitting of d orbitals.

Example for strong-field ligand: CO Example for weak-field ligand:  ${\mathrm{Cl}}^{-}$