(142p) Control of Crystal Structure and Its Defect of Ε-Hniw Prepared by Evaporation Crystallization

The ε-hexanitrohexaazaisowurtzitane (HNIW) single crystals were prepared by slow evaporation and the structural defect of the crystal was measured with density gradient column. Structure of crystal, defect and size depended on the condition of crystallization such as, initial concentration of solution, evaporation rate and solvent. As things turned out, defect of crystals were increased according as elevation of evaporation rate. Nevertheless, defect of crystals didn't nearly take the influence of evaporation rate over the 40°C and it was comparatively revealed homogeneously. Also, On the highly evaporation rate at 70°C, defect of crystals had taken β-form crystal that has low density more than ε-form crystal. On the condition of the highly concentration of HNIW, we could see that some crystal to be produced crystal contained a lot of defect compared with crystal which produced in the low concentration of HNIW.And the defect of crystal took influence of inert solvent at the crystallizer.