This article provides a detailed account of the concepts of single-crystal x-ray diffraction (XRD). It begins with a historical review of XRD methods, followed by a description of the various factors involved in crystal symmetry. The article then focuses on the phase problem in x-ray structural analysis and validation of the structural model. Some of the factors to be considered for performing experimental procedure are provided. The article presents several examples of applications of single-crystal XRD. The following sections cover the crystallographic problem in terms of structural analysis, software programs for crystal structure solution and refinement, and visualization of crystal structures. The article ends with a discussion on various databases available for single-crystal XRD analysis.

Microstructural analysis is the combined characterization of the morphology, elemental composition, and crystallography of microstructural features through the use of a microscope. This article reviews three types of the most commonly used electron microscopies in metallurgical studies, namely scanning electron microscopy, electron probe microanalysis, and transmission electron microscopy. It briefly describes the operating principles, instrumentation which includes energy dispersive X-ray detectors, spatial resolution, typical use of the techniques, elemental analysis detection threshold and precision, limitations, sample requirements, and the capabilities of related techniques.

X-ray powder diffraction (XRPD) techniques are used to characterize samples in the form of loose powders or aggregates of finely divided material that readily diffract x-rays in specified patterns. This article provides an introduction to XRPD, beginning with a review of sensing devices, including pinhole/Laue cameras, Debye-Scherrer/Gandolfi cameras, Guinier cameras, glancing angle cameras, conventional diffractometers, thin film diffractometers, Guinier diffractometers, and micro diffractometers. The article then describes several quantitative measurement methods, such as lattice parameter, absorption diffraction, spiking, and direct comparison, explaining where each may be used. It also identifies potential sources of error in XRPD measurements.