Ionic radius
The key idea
Ionic radius is an effective size assigned to an ion within a structural or bonding model, commonly derived from interionic distances in crystals.
Why it matters
Cations are often smaller than their neutral atoms and anions often larger, but coordination number and oxidation state can strongly affect tabulated values.
A picture to remember
Cations are often smaller than their neutral atoms and anions often larger, but coordination number and oxidation state can strongly affect tabulated values.