Prediction of densities for solid energetic molecules with molecular surface electrostatic potentials

Abstract

The densities of high energetic molecules in the solid state were calculated with a simplified scheme based on molecular surface electrostatic potentials (MSEP). The MSEP scheme for density estimation, originally developed by Politzer et al., was further modified to calculate electrostatic potential on a simpler van der Waals surface. Forty-one energetic molecules containing at least one nitro group were selected from among a variety of molecular types and density values, and were used to test the suitability of the MSEP scheme for predicting the densities of solid energetic molecules. For comparison purposes, we utilized the group additivity method (GAM) incorporating the parameter sets developed by Stine (Stine-81) and by Ammon (Ammon-98 and -00). The absolute average error in densities from our MSEP scheme was 0.039 g/cc. The results based on our MSEP scheme were slightly better than the GAM results. In addition, the errors in densities generated by the MSEP scheme were almost the same for various molecule types, while those predicted by GAM were somewhat dependent upon the molecule types.

A DFT study on the structure–property relationship of amino-, nitro- and nitrosotetrazoles, and their N-oxides: new high energy density molecules

“…The higher densities of tetrazole-N-oxides are presumably due to the intramolecular hydrogen bonds as well as the layered structures in the crystal lattice. Nevertheless, the absolute error in the calculated densities of designed compounds are expected to be less than 0.03 g/cm 3 and thus known to be fairly good to calculate performance properties [36][37][38][39][40][41].…”

“…However, the detonation pressure varies with the square of density, when the density is greater than one. Several researchers have attempted to predict the densities with satisfactory accuracy [37][38][39][40][41].…”

Improved method for prediction of density of energetic compounds using their molecular structure

“…Since reliable prediction of density of an energetic compound is the utmost important for estimation of its performance, different approaches were developed to predict densities of energetic compounds, which have been reviewed elsewhere [14,15]. Quantum mechanical calculations require high-speed computer to conduct complicated calculations, which can be used for energetic molecules with simple molecular structures [16][17][18][19][20]. Among different quantum mechanical methods, Qiu et al [17] introduced a very direct approach to estimate the crystal densities of nitramines on the basis of the ratio of the molecular mass, in g/molecule, and the volume of the isolated gas phase molecule, in cm 3 /molecule.…”

Prediction of the Density of Energetic Materials on the Basis of their Molecular Structures

“…Kim et al have suggested that a prediction that differs by less than 0.03 g/cm 3 from the experimental value should be defined as 'excellent', while one that is between 0.03 and 0.05 g/cm 3 in error is still 'informative' [12]. For estimating the crystal density of available energetic materials, various methods have been developed.…”

“…For estimating the crystal density of available energetic materials, various methods have been developed. These include electrostatic potentials using quantum-mechanically determined molecular volumes [11][12][13][14][15], group additivities [8,9,[16][17][18], empirical methods [19][20][21][22] and Quantitative Structure-Property Relationships (QSPR) [23].…”