Back-reflection x-ray crystallography method and system

A back-reflection X-ray diffraction system comprising:

• an X-ray generator;
• a back-reflection Laue camera system comprising an X-ray detector, camera, base and three-axis rotation goniometer;
• the X-ray generator and camera system being operatively connected to a computer system;
• the computer system comprising a processor, computer memory, at least one input device, at least one display, the processor and memory configured to operate the X-ray generator and camera system to perform X-ray diffraction of a specimen by performing the steps of:
• setting an approximate pre-selected X-ray detector to specimen distance (hereafter called “film-to-specimen distance”);
• subjecting the specimen to X-rays;
• recording the back-reflected Laue diffraction pattern;
• calculating the Miller indices of a predetermined fraction of the spots in the resulting pattern;
• averaging the Miller indices of the fraction of spots;
• moving a virtual representation of the specimen by a predetermined small amount along a line connecting the film to the specimen, changing the film-to-specimen distance;
• repeating the calculation, averaging and moving in small angular steps until the virtual representation of the specimen has been moved through a predetermined small distance range and best fits to the observed data;
• and
• determining the optimum film-to-specimen distance resulting in the smallest average Miller index.