Chemistry
Why Strong Field Ligands Increase Crystal Field Splitting
Quick fact
Ligands like CO and CN⁻ are called strong field ligands because they create a large energy gap between the t₂g and eg orbitals, often forcing electrons to pair up and yielding low-spin complexes, unlike weak field ligands like I⁻ or Br⁻.
Why this is interesting
You know that some metal complexes are intensely colored while others are pale, and some are magnetic while others are not. Why does the simple change of a ligand from water to cyanide radically alter the complex's properties?