This book provides an introduction to crystallography, light, X-ray, and electron diffraction. The book also shows, by historical and biographical references, how the subject has developed from the work and insights of successive generations of crystallographers and scientists. The book shows how an understanding of crystal structures, both inorganic and organic may be built up from simple ideas of atomic and molecular packing. Beginning with (two-dimensional) examples of patterns and tilings, the concepts of lattices, symmetry point, and space groups are developed. ‘Penrose’ tilings and quasiperiodic structures are also included. The reciprocal lattice and its importance in understanding the geometry of light, X-ray, and electron diffraction patterns is explained in simple terms, leading to Fourier analysis in diffraction, crystal structure determination, image formation, and the diffraction-limited resolution in these techniques. Practical X-ray and electron diffraction techniques and their applications are described. A recurring theme is the common principles: the techniques are not treated in isolation.

This study investigates a range of commercially available γ‐Al2O3 powders by using a combination of integrated experimental techniques. These included general measurements of powder properties by using helium density, BET surface area, and scanning electron microscopy (SEM) analyses. In addition, dynamic light scattering and zeta potential measurements were used to investigate nanoparticle dispersions. Bulk crystal structures were analysed by using comparative X‐ray and neutron powder diffraction (XRD and NPD) analyses. Conventional transmission electron microscopy (TEM) was used to determine particle morphology, particle size, composition, and structure. Aberration‐corrected TEM was used to investigate the crystallinity of nanoparticles including the existence of any surface reconstruction on commonly observed facetted, cubeoctahedral γ‐Al2O3 nanoparticles. From the observation of peak splittings in diffraction data, we favour a description of the γ‐Al2O3 structure based on a distortion of the conventionally accepted face‐centred cubic (Fd$\bar 3$m) structure into a tetragonal I41/amd structure. Distinct differences between TEM, XRD, and NPD data indicate the presence of some cation disorder within a rigid close‐packed oxygen framework. The Rietveld refinement of the NPD data suggests a high level of microstrain of 1.2 %. An improvement to the model is achieved by reducing the aluminium content in the unit cell, which is commensurate with the migration of aluminium ions to the surface and some degree of nonstoichiometry in the particle core. Aberration‐corrected TEM imaging and exit wave reconstruction confirm previous evidence for the presence of enhanced surface contrast at {1 1 1} surface facets, which we associate with the presence of excess cation termination. In addition, these {1 1 1} facets are observed to be heavily stepped. These results may have important implications for the thermal stability of metal catalyst nanoparticles on these high‐surface area supports; the migration of aluminium ions to the surface provides clear evidence of why these materials perform so well as catalyst supports.

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This revised edition of a book which forms a part of the International Union of Crystallography's series of Texts on Crystallography is some 30% larger than its predecessor, amongst other reasons because of increased coverage of diffraction and the inclusion of a separate chapter on the stereographic projection. Overall Dr Hammond covers the topics one would expect from the title. It is particularly pleasing to see considerable emphasis placed on symmetry, a topic that is fundamental to crystallography but is all too often played down these days in elementary courses because of the demands it makes on students' ability to appreciate matters that are underpinned by rigorous mathematical arguments, even when, as here, the formalities are replaced by persuasive text. Indeed the level of the mathematics in the book has deliberately been kept simple. The expanded chapters on diffraction cover the basic theoretical background for x-ray and electron diffraction, with a brief reference to neutron diffraction, illustrated by reference to a range of experimental methods. Perhaps the selection might have given greater emphasis to counter-diffractometry and computer-based data analysis rather than to photographic methods but the latter are arguably better at illustrating important geometrical aspects of data collection. Each chapter is rounded off with a helpful set of exercises, for which detailed answers are provided at the end of the book.A separate strand that runs throughout the book informs the reader about the history of the subject from its early days to the present, culminating in appendix 3, which presents brief biographies of almost 50 figures influential in the development of crystallography and diffraction, many of whom are remembered daily, without appreciation of their human side, because their names are attached to important parts of the theoretical or practical `apparatus' of the subject. Other appendices contain helpful information about sources of components for crystal model-building and about useful software as well as information on a number of geometrical and mathematical topics.Finally, one name in particular leapt out from the author's acknowledgments: the reviewer too acknowledges with gratitude the guidance of Dr Norman Henry many years ago!In short, this book is an excellent attempt to present in an interesting yet simple way a subject that many students find daunting. It well deserves to succeed.John A Leake