A Procedure for Estimating the Crystal Densities of Organic Explosives
Abstract
High density is an important property for a military explosive. The quantity of material that can be carried in a space-limited warhead, and performance parameters such as detonation pressure and velocity, increase with density. An accurate and reliable method for calculating the solid state (crystal) density from the molecular formula of an energetic material would permit predictions to be made of explosive performance and serve as a valuable adjunct to any synthesis program aimed at producing improved explosive compounds. The compounds of most interest as military explosives often have densities significantly above the norm and predicted densities for members of this group frequently are substantially underestimated. A new procedure has been developed that allows a possible crystal packing arrangement for a molecule to be determined, from which a crystal density, usually accurate to within 2%, can be calculated. The techniques consists of three parts: 1) determination of a reasonable three-dimensional molecular structure; 2) determination of several possible crystal packing arrangements (crystal structures) for this molecular structures; 3) refinement of the unit cell parameters, molecular orientation and position for each of the potential crystal structures. The lowest energy arrangement from step (3) is used to calculate the crystal density. The crystal densities predicted for both bicyclo-HMX and octanitrocubane are lower than those obtained from additivity methods.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1987
- Accession Number
- ADA189023
Entities
People
- Don T. Cromer
- Herman L. Ammon
- James R. Holden
Organizations
- Los Alamos National Laboratory