Diffusion Missiles are essentially the charge beam equivalent of missiles. Like the Diffusion Beam, the projectile will burst into a wide radius on impact, and destroy everything within its reach. However, these destructive properties are not directly viewed, as the Diffusion Missile is never seen without the Ice Missile upgrade. Samus obtains it shortly after defeating Nightmare.
When paired with Ice Missiles, the blast will freeze every enemy in sight that is freezable.