CL-20 and HMX are both powerful explosives. CL-20 produces a more powerful blast but is generally considered too shock-sensitive for practical use. HMX is significantly less sensitive and is used as a standard military explosive. When a 2:1 mixture of the two compounds is cocrystallized, the resulting explosive is expected to be more powerful than HMX alone, but with a sensitivity similar to HMX (Cryst. Growth Des. 2012, 12, 4311–4314).
(b) Consider the lone pair of electrons on one of the nitrogen atoms within the ring(s) for either molecule. Is the lone pair localized or delocalized?