Unknown crystal structure determination from X-ray powder diffraction data

The crystal structure of new compound Ba3BPO7 has been solved by X-ray powder diffraction technique. As a new structure type, the positions of barium, boron and phosphate atoms have been determined by single crystal direct method after profile decomposition from Ba3BPO7 X-ray powder diffraction patterns. The positions of oxygen atoms have been determined by the interpretation of their vibration spectra which indicate that in this crystal the boron and phosphorus atoms form BO3 and PO4 polyhedra. The structure has been refined by Rietveld technique based on the above model.