Reasons behind the different colors of a solution containing Iodine
Iodine in an inert solvent is purple.  Electron donation alters that.  Linear starch (amylose)-iodine is dark brown.  Branched starch (amylopectin)-iodine is red.  The Wikipedia page shows iodine in chlorinated solvent (very weak electron donation) then addition of strong electron donor triphenylphosphine.

If an electron donor is reactive, then the interacting iodine molecule looks like iodonium (elecron accepter).  Initial interation is (4), post-mixing is (3).

Put a tiny iodine crystal into a melting point capillary, evacuate under vacuum, flame closed.  You will see a very pale purple vapor at equilibrium.  Crack the seal and the vapor is suddenly deeper purple.  Why?  Take a sealed cap and an evacuated sealed cap, and insert the vapor volumes into the beam of a green laser pointer. interesting. Take care that the optical geometry does not reflect back into your eyes.