AbstractThe occurrence of [100] direction slip on the (021) slip plane of orthorhombic RDX (cyclotrimethylenetrinitramine, (CH2·N·NO2]3) is shown to favor the formation of 1,3-dinitroso-5-nitro-l,3,5-triazacyclohexane, as detected in drop-weight impact tests at sensitivity height levels near to those measured for initiation. Also, the reported observation of deformation twinning in the chemically-related monoclinic HMX (cyclotetra-methylenetetranitramine, (CH2·N·NO2 ]4) crystal lattice is explained on the basis of the greater flexibility of the larger HMX molecule allowing a number of bond rotations that are required to produce a relatively unusual Type II deformation twinning structure. These examples give support to the consideration that on the molecular level involved in deformation-induced decompositions there may be a direct mechanical force aspect that is additional to the established importance of “hot spot” heating, say, as described for dislocation pile-up avalanches in RDX.
A Fallback Accretion Model for the Unusual Type II-P Supernova iPTF14hls