Structures of nanometre-size crystals determined from selected-area electron diffraction data

The structure of a new modification of Ti,Se, the B-phase, and several rela ted inorganic crystal structures containing elements with atomic numbers be tween 16 and 40 have been solved by quasi-automatic direct methods from sin gle-crystal electron diffraction patterns of nanometre-size crystals, using the kinematical aproximation. The crystals were several thousand times sma ller than the minimum size required for single-crystal X-ray diffraction. A tomic coordinates were found with an average accuracy of 0.21 Angstrom or b etter. Experimental data were obtained by standardized techniques for recor ding and quantifying electron diffraction patterns. The SIR97 program for s olving crystal structures from three-dimensional X-ray diffraction data by direct methods was modified to work also with two-dimensional electron diff raction data.