Deciphering the driving forces in low-sensitivity and high-energy materials by data mining: Insights into π-hole interactions

A data mining investigation on more than 2000 crystals of energetic materials (EMs) was conducted to figure out the influences of π-hole interactions on crystal packing and related performances. The statistical analysis results show that π-hole interactions are discovered in about 75 % of EMs with crystal density of greater than 1.7 g/cm3, even in 87 % of the low-sensitivity and high-energy crystals in this work. The π-hole interactions have moderate interaction strength (up to 6 kcal/mol sometimes) that is linearly correlated to the most positive surface electrostatic potential of π-hole, and correspondingly we proposed two essential conditions to form π-hole interactions in view of topology and electronic structures. The results reported herein decipher the importance of π-hole interactions in constructing low-sensitivity and high-energy materials, which have been seldom reported in the previous studies of EMs. In addition to hydrogen bonds and π-π stacking interactions, therefore, π-hole interactions should be acted as another key factor to design supramolecular synthon for the crystal engineering of advanced EMs.