Structure determination from powder diffraction data [[electronic resource] /] / edited by W.I.F. David ... [et al.]

• Record Nr.: UNINA9910464864003321
• Pubbl/distr/stampa: Oxford ; ; New York, : Oxford University Press, 2002
• ISBN: 9786611370183; 1-281-37018-5; 0-19-152556-1
• Descrizione fisica: 1 online resource (358 p.)
• Collana: IUCr monographs on crystallography ; ; 13
• Altri autori (Persone): DavidW. I. F (William I. F.)
• Disciplina: 548
• Soggetti: X-ray crystallography; Crystals - Structure; Powders - Optical properties - Measurement; Electronic books.
• Lingua di pubblicazione: Inglese
• Formato: Materiale a stampa
• Livello bibliografico: Monografia
• Note generali: Description based upon print version of record.
• Nota di bibliografia: Includes bibliographical references and index.
• Nota di contenuto: Contents; List of contributors; 1 Introduction; 1.1 Crystal structures from powder diffraction data; 1.2 The structure determination process; 1.3 Adapting single-crystal structure solution methods to powder diffraction data; 1.4 Direct-space methods that exploit chemical knowledge; 1.5 Hybrid approaches; 1.6 Outlook; Acknowledgements; References; 2 Structure determination from powder diffraction data: an overview; 2.1 Introduction; 2.2 Early history of powder diffraction; 2.3 Early ab initio approaches; 2.4 Pre-Rietveld refinement methods; 2.5 Rietveld refinement; 2.6 Solving unknown structures from powder data2.7 Trial-and-error and simulation methods; 2.8 Some examples of structure determination from powder data; 2.9 Conclusions; References; 3 Laboratory X-ray powder diffraction; 3.1 Introduction; 3.2 The reflection overlap problem; 3.2.1 Instrumental broadening-g(2θ); 3.2.2 Sample broadening-f[sub(hkl)](2θ); 3.2.3 H(x) profiles; 3.3 Instrumentation and experimental considerations; 3.3.1 Diffractometer geometries; 3.3.2 Monochromatic radiation; 3.3.3 Data quality; 3.4 Examples of crystal structure solution; 3.4.1 Bragg-Brentano powder diffraction data3.4.2 Debye-Scherrer powder diffraction data; 3.5 Conclusions; Acknowledgements; References; 4 Synchrotron radiation powder diffraction; 4.1 Introduction; 4.2 Synchrotron powder diffraction instruments in use for ab initio structure determination; 4.3 Angular resolution, lineshape and choice of wavelength; 4.4 Data preparation and indexing; 4.5 Pattern decomposition and intensity extraction; 4.6 Systematic errors; 4.6.1 Particle statistics; 4.6.2 Preferred orientation; 4.6.3 Absorption; 4.6.4 Extinction; 4.7 Examples of structure solution; 4.7.1 Pioneering studies4.7.2 Organic compounds; 4.7.3 Microporous materials; 4.7.4 Organometallics; 4.7.5 More difficult problems; 4.8 Conclusions; Acknowledgements; References; 5 Neutron powder diffraction; 5.1 Introduction; 5.2 Instrumentation; 5.3 Autoindexing and space group assignment; 5.4 Patterson methods; 5.5 Direct methods; 5.6 X-n structure solution; 5.7 Future possibilities; References; 6 Sample preparation, instrument selection and data collection; 6.1 Introduction; 6.2 Issues and early decisions-experimental design; 6.3 Multiple datasets; 6.4 The sample; 6.4.1 Sources of sample-related errors6.4.2 Number of crystallites contributing to the diffraction process; 6.4.3 Increasing the number of crystallites examined; 6.4.4 Generating random orientation; 6.4.5 Removing extinction; 6.5 The instrument; 6.5.1 What radiation to use-X-rays or neutrons?; 6.5.2 What wavelength to use?; 6.5.3 Number of 'independent' observations (integrated intensities); 6.5.4 What geometry to use?; 6.5.5 Sources of instrument-related error; 6.6 Data collection; 6.6.1 Step time and width recommendations; 6.6.2 Variable counting time data collection; 6.7 Conclusions; References
• Sommario/riassunto: Our understanding of the properties of materials, from drugs and proteins to catalysts and ceramics, is almost always based on structural information. This book describes the developments in powder diffraction which make it possible for scientists to obtain such information, and guides both novices and practitioners through all the possibilities. - ;The art of solving a structure from powder diffraction data has developed rapidly over the last ten years to the point where numerous crystal structures, both organic and inorganic, have been solved directly from powder data. However, it is still a