AB INITIO PREDICTION OF NEW ENERGETIC MATERIALS WITH LOW IMPACT SENSITIVITIES
Abstract
Amongst the most important characteristics of an energetic material is its propensity to initiate on mechanical or thermal perturbation. At present, it is necessary to first synthesise a candidate energetic material and then experimentally probe its sensitivity. Without a priori knowledge of material sensitivity the preparation of these compounds is associated with considerable risk to safety. Moreover, the experimental conditions themselves have been welldocumented to be prone to variability due to external parameter conditions and user operator experience. If impact sensitivity could be predicted prior to material synthesis it represents a step-change opportunity in the search for new energetics that are safe to handle. It also opens up opportunities to understand the relationship between chemical structure and material properties, which in turn fuels the design of next generation materials. We have very recently demonstrated that impact sensitivity is a predictable metric by first principles simulation, provided the crystal structure of a material is known. Now we seek to build on this success by bringing crystal structure prediction methods into our work-flow. Thus we will have at our disposal all the computational modelling protocols needed for a new energetic materials screening programme. This proposal rests on three objectives: 1. Molecular energy screening: Molecules are screened for large energetic power via calculation of formation energies using first principles simulation methods. 2. Crystal structure prediction: Molecules identified in the energy screening study are taken forward for crystal structure prediction using state-of-the-art methods developed in-house. 3. Impact sensitivity prediction: Predicted crystal structures will then be subjected to first principles optimisation, calculation of vibrational densities of states, and processing using our in-house protocols to generate predicted impact sensitivity metrics. This project has the potential to screen 20-30 new energetic materials with predicted impact sensitivity behavior which could then be taken forward for experimental investigation.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 11, 2021
- Source ID
- FA86552017000
Entities
People
- Carole A. Morrison
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Edinburgh