TY - JOUR A1 - Michalchuk, Adam A1 - Trestman, M. A1 - Rudic, S. A1 - Portius, P. A1 - Fincham, P. A1 - Pulham, C. A1 - Morrison, C. T1 - Predicting the reactivity of energetic materials: an ab initio multi-phonon approach JF - Journal of Materials Chemistry A N2 - The ease with which an energetic material (explosives, propellants, and pyrotechnics) can be initiated is a critical parameter to assess their safety and application. Impact sensitivity parameters are traditionally derived experimentally, at great cost and risk to safety. In this work we explore a fully ab initio Approach based on concepts of vibrational energy transfer to predict impact sensitivities for a series of chemically, structurally and energetically diverse molecular materials. The quality of DFT calculations is assessed for a subset of the materials by comparison with experimental inelastic neutron scattering spectra (INS). A variety of models are considered, including both qualitative and quantitative analysis of the vibrational spectra. Excellent agreement against experimental impact sensitivity is achieved by consideration of a multi-phonon ladder-type up-pumping mechanism that includes both overtone and combination pathways, and is improved further by the added consideration of temperature. This fully ab initio approach not only permits ranking of energetic materials in terms of their impact sensitivity but also provides a tool to guide the targeted design of advanced energetic compounds with tailored properties. KW - Energetic Materials KW - Prediction KW - Density Functional Theory PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-489328 DO - https://doi.org/10.1039/c9ta06209b VL - 7 IS - 33 SP - 19539 EP - 19553 PB - RSC AN - OPUS4-48932 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Michalchuk, Adam A1 - Rudic, S. A1 - Pulham, C. A1 - Morrison, C. T1 - Predicting the impact sensitivity of a polymorphic high explosive: the curious case of FOX-7 JF - Chemical Communications N2 - The impact sensitivity (IS) of FOX-7 polymorphs is predicted by phonon up-pumping to decrease as layers of FOX-7 molecules flatten. Experimental validation proved anomalous owing to a phase transition during testing, raising questions regarding Impact sensitivity measurement and highlighting the need for models to predict IS of polymorphic energetic materials. KW - Energetic materials KW - Density functional theory KW - Inelastic Neutron Scattering Spectroscopy KW - Impact Sensitivity PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-535558 DO - https://doi.org/10.1039/d1cc03906g SN - 1364-548X VL - 57 IS - 85 SP - 11213 EP - 11216 PB - Royal Society of Chemistry AN - OPUS4-53555 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -