中性硝基分子几何形状与晶体特性的关联性OA北大核心CSTPCD

The packing structure of energetic crystals is one of the important factors affecting their sensitivity.A crucial mecha-nism for reducing the sensitivity of energetic materials is buffering external stimuli through the slipping between molecular layers within the crystal.It is very important to understand the inherent relationship between the geometric shape of energetic mole-cules and their crystal properties for the better design of low sensitivity high energetic materials(LSHEs).This study used neutral CHNO molecules containing nitro from the Cambridge Structural Database as samples.Hypothesis testing methods(including Z-,t-,and χ2 tests)were employed to investigate the correlation between the geometric shape of molecules and their crystal den-sity,packing coefficient,and slipping ability.The study shows that among spherical,planar and linear molecules:spherical molecules have the highest crystal density and packing coefficient,but weaker slipping ability;planar molecules with high pla-narity achieve a crystal density comparable to spherical molecules by a high packing coefficient,while also exhibiting stronger crystal slipping ability,its confidence level of the χ2 test is close to 1;linear molecules perform less well than the former two.Though some crystals with high crystal density and packing coefficient do not have slipping ability,general speaking,the crystal density and packing coefficient of the crystals with slipping ability are higher than those without.Both Z-tests and t-tests indicate a confidence level exceeding 0.95,suggesting that designing crystal structures conducive to intermolecular-layer slipping is not contradictory to reduceing their sensitivity and increasing crystal density.Planar molecules have a higher crystal density than av-erage,and it is strongly associated with crystal slipping ability,making them the preferred choice for designing LSHEs.