The results of these studies will provide valuable information on the effects of temperature on the structures of an energetic salt and co-crystal formed between nitrotriazolone and bipyridine, and in particular whether temperature-induced proton transfer is responsible for the observed colour change. This insight into the structural data obtained will strengthen our knowledge of the relationship between molecular packing and sensitivity to impact and shock. The high-quality structural data that will be obtained, including the effects of temperature on hydrogen-bonding motifs, will provide insight into molecular energy transfer, detonation mechanisms and, particularly in this case, the sensitivities to initiation. The results will also be of significant interest to theoreticians who seek to develop predictive models of the behaviour of energetic materials under operational conditions.