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Crystal density is a basic and important parameter for predicting the detonation performance of explosives, and nitrate esters are a type of compound widely used in the military context. In this study, thirty-one aliphatic nitrates were investigated using the density functional theory method (B3LYP) in combination with six basis sets (3-21G, 6-31G, 6-31G*, 6-31G**, 6-311G* and 6-31+G ** ) and the semiempirical molecular orbital method (PM3). Based on the geometric optimizations at various theoretical levels, the molecular volumes and densities were calculated. Compared with the available experimental data, the densities calculated by various methods are all overestimated, and the errors of the PM3 and B3LYP/3-21G methods are larger than those of other methods. Considering the results and the computer resources required by the calculations, the B3LYP/6-31G* method is recommended for predicting the crystalline densities of organic nitrates using a fitting equation. The results obtained with this method are slightly better than those reported by Keshavarz and Rice. In addition, the effects of various groups (such as -ONO2, -OH, -Cl, -O-, and -CH2-) on the densities are also discussed, which is helpful for the design of new molecules in terms of practical requirements. Nomenclature: D difference between the predicted and experimental densities [g·cm IntroductionCurrently, the study of novel high energy density materials (HEDMs) is one of the most active regions of research and seems to be never ending because of the superior explosive performances of HEDMs compared to the currently used materials [1-3]. Density is a primary physical parameter, closely related to the explosive performances such as detonation velocity and pressure, explosion heat, and specific volume. Since detonation velocity and detonation pressure increase proportionally with the density and the square of the density, respectively [4,5], improving the density is the main approach to discovering new HEDMs at present. It is thus very important to obtain the density of proposed new compounds.Among the methods previously used to predict the crystalline density (ρ exp ) of explosives, the simplest, earliest and most widely used one is the group additivity method of the molar refraction [5] and the molar volume [6,7], where the molar volume is obtained by summing up the volumes of atoms or functional groups. These methods can rapidly predict the volume and density. However, they have limitations in accounting for the molecular conformation, isomerization, and crystal packing efficiency.Researchers [8][9][10][11][12][13] have also been attempting to use the potential function and crystal chemistry methods, based on the dense packing theory, to predict crystalline densities more accurately. These approaches can effectively account for the influence of the molecular spatial arrangement, but they require extensive computational work and take more computer time and higher costs, which makes it difficult for wide application. developed some new correlations to...

Polyglycerine polynitrates such as nitroglycerine can be used as energetic plasticizers of propellants. In this study, 29 derivatives of nitroglycerine are investigated at the B3LYP/6-31G* level of the density functional theory. The corrected theoretical densities ([Formula: see text]) are predicted and are found to be very close to the experimental values. Detonation properties are calculated using the modified Kamlet–Jacobs equations and the specific impulse (Is) is evaluated according to the maximum exothermic principle. A new parameter K, which is the product of Is and [Formula: see text], is proposed to evaluate the overall energetic characteristics of compounds. Thermal stability is discussed by calculating the bond dissociation energies or bond dissociation energy barriers. The O–NO2 bond has the smallest bond dissociation energy and is the trigger bond for each of the studied compounds. The influence of the –ONO2 and –CH2–O–CH2–CH(ONO2)– groups, which is useful for design of new high energy plasticizers, is also discussed. Comprehensively considering the energetic properties and the stability, DGPN, DGHN, TriGHeptaN, TriGON, TriGNN, TetraGNN, TetraGDeN, TetraGUN, and TetraGDoN are possibly better energetic plasticizers of solid propellants than nitroglycerine.