MOLECULAR MECHANIC SIMULATION OF THE CRYSTAL STRUCTURES OF HMX AND CL-20 USING THE FORCE FIELD COMPASS - A COMPARISON WITH MEASURED DATA

摘要

The fundamental computation of a force field-based simulation is the calculation of the potential energy for a given configuration of atoms or cells. The calculation of this energy, along with its first and second derivatives with respect to the atomic coordinates or cell coordinates, yields the information necessary for minimization, vibration analysis, and dynamics simulations. Nitramines are an important group of energetic materials. The crystal structures of the stable modifications of HMX and HNIW (CL-20), p-HMX and e-HNlW, were taken as basis for the molecular mechanical simulations using the second generation force field COMPASS. The geometric parameters of the molecules of the two crystal structures were compared with those obtained by simulations and discussed in detail.