Structure Determination from Powder Diffraction Data - It Is Unrealizable Dream or Daily Use?

Abstrakt

There are available several methods, which can be used for crystal structure determination (X-ray structure analysis, neutron structure analysis and others). The most common one is single-crystal X-ray diffraction. This method is often inapplicable because it is impossible to prepare single crystal of appropriate size or quality. In these situations we are forced to solve structure from powder diffraction data. However structure determination from powder diffraction data brings a lot of problems (loss of information, peak overlapping, preferred orientation, phase in-purity etc.). In spite of all these problems it is possible to use this method for structure solving. This work aims to highlight all problems presented in structure determination process from powder diffraction data. We describe all steps of the powder-structure determination procedure and we highlights the non-standard experimental and data processing methods used for this task (synchrotron radiation usage, multi PC data processing, utilizing of information obtained form non-diffraction sources ?).The results of structure determinations from powder data are demonstrated on several selected examples from recent time.