Once again on the shock impact topic. In her new nice manuscript in Scientific Reports Mara Murri presents some of the recent considerations about structural disorder in the form of complex combinations of cubic and hexagonal stacking motifs commonly occurring on impact diamonds which structural characterization remains an extremely challenging task.
In this study impact diamonds from the Popigai crater have been characterized with a range of techniques. With MCDIFFaX on the X-ray diffraction data, we found hexagonality indices up to 40%. Furthermore, electron microscopy revealed nanoscale twinning within the cubic diamond structure. These results lead us to propose a systematic protocol for assigning specifc hexagonality attributes to the mineral under investigation