This chapter discusses the theoretical background and the practical tools for solving structures from powder-diffraction data using reciprocal-space methods. In particular, it describes the basic concepts of direct methods, Patterson methods, charge flipping and maximum-entropy methods. Developments of these methods aimed at coping with the problems typically facing structure solution using powder-diffraction data (e.g. peak overlap, preferred orientation) are also discussed. A brief description is also given of current software packages based on reciprocal-space techniques in which constantly evolving theories are implemented. Examples using some of these packages are given, and raw powder-diffraction data for some of the examples can be downloaded and explored.
Solving crystal structures using reciprocal-space methods In International Tables for Crystallography Volume H: Powder Diffraction
A Altomare;C Cuocci;A Moliterni;R Rizzi
2019
Abstract
This chapter discusses the theoretical background and the practical tools for solving structures from powder-diffraction data using reciprocal-space methods. In particular, it describes the basic concepts of direct methods, Patterson methods, charge flipping and maximum-entropy methods. Developments of these methods aimed at coping with the problems typically facing structure solution using powder-diffraction data (e.g. peak overlap, preferred orientation) are also discussed. A brief description is also given of current software packages based on reciprocal-space techniques in which constantly evolving theories are implemented. Examples using some of these packages are given, and raw powder-diffraction data for some of the examples can be downloaded and explored.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.