SYNCHROTRON WHITE-BEAM X-RAY TOPOGRAPHY CHARACTERIZATION OF DEFECT STRUCTURES IN 2,10-UNDECANEDIONE UREA INCLUSION-COMPOUNDS/

The defect structure of a crystal of the urea inclusion compound (UIC) of 2,10-undecanedione was investigated using Synchrotron White Beam X -ray Topography. X-ray transmission topographs recorded from different regions show that the crystal is divided into several twin domains. E ach region in the crystal is revealed on the topographs by orientation contrast arising from the mutual misorientation of adjacent regions. Using a combination of pinhole Lane pattern analysis and topographic o rientation contrast analysis, the twin operation was determined to be consistent with an approximately 60 degrees rotation about the orthorh ombic c-axis. Possible twin boundary structures are also presented. Ot her defects such as dislocations and inclusions are also characterized .