Liquid Ions and Boron Nitride. Hexagonal. Cubic. Importance of AlCl3. AlCl 3 is in a dynamic equilibrium with Al 2 Cl 6 Al 2 Cl 6 2AlCl 3 It has a high affinity for chlorine This allows it to act a catalyst in the Friedel-Crafts reaction, in this case for the chlorination of benzene.