1. Возможности разных геометрических систем при одной и той же полной совокупности элементов

2. Существование безграничного множества геометрических систем

3. Очерк месторождений железных руд западной части центральной России и Царства Польского

4. Определение величины двупреломления

5. Следы проявления триклинной сингонии в ортоклазе

6. К вопросу о происхождении двойниковых полосок в пикроклине

7. Линейная прима кривых поверхностей 2-го порядка (коносекунд), определяемая одного из них и плоскостью

8. Сдвиг обыкновенных и полярных решеток

9. Опыты по кристаллизации между двумя сферами

Crystals are solid materials having regular atomic arrangements characterized by periodicity and anisotropy. These properties are universally present, irrespective of whether the crystal is inorganic or organic, in living systems or in the inanimate world. Crystals exhibit various external forms, as represented by the elaborately varied dendritic forms of snow crystals or the hexagonal prismatic forms of rock-crystal. This variety of shape has stimulated scientific curiosity since the seventeenth century, since when intensive efforts have been made to understand the reasons why and how crystals can take a variety of forms <...>

This is volume five in the series of picture books that I am creating for educational purposes. All images in this volume were created using the program JPOWD from MDI (www.materialsdata.com). The structures presented here correspond to the crystal structure gallery on my website (www.jcrystal.com/steffenweber/gallery/StructureTypes/st1.html). On that website you can also find further data, such as unit cell parameters and atom coordinates . 

Let us begin with the question: What is a pattern? The answer to this question is as much objective as it may be subjective. From the days unknown, the human race have started studying and appreciating the regular periodic features like movement of stars, moon, sun, the beautiful arrangement of petals in flowers, the shining faces of gems, and also the beautiful wings of a butterfly.

This fully revised and updated edition has been prepared by a very active worker in the field, who has used previous editions extensively both in teaching and in research, together with one of the original authors. Since the first edition, written in the late 1960s, understanding of crystal defects such as dislocations, stacking faults, twin, grain and interphase boundaries and of their effect on the mechanical and electrical properties of materials has grown enormously and has been accompanied by a total change in style of the way in which both research and teaching are carried out through the use of the fast digital computer. This edition takes account of this change. <...>

Despite such a wide abundance of crystals, it was not until the 17th century, with the move towards modern scientific rationalism, that the first real successes in understanding their nature since the times of the ancient Greeks were attained. It was the era of the Enlightenment that led to the systematic study of crystals or ‘crystallography’, the term having been coined by a Swiss physician, Maurice Capeller (1685–1769). <...>

Translational symmetry is firmly established as the key property characterizing the crystalline state of matter. This is founded in the successes of translational symmetry in explaining physical properties of crystalline compounds and Bragg reflections in their diffraction patterns, as well as in the many substances that possess periodic atomic structures. An alternative and perhaps better characterization of the crystalline state is by long-range order of the atomic structure. The past fifty years have seen a continuous increase of the awareness that long-range order can be achieved differently than by translational symmetry. Modulated crystals and composite crystals have atomic structures that can be described as variations on periodic structures, while quasicrystals differ from crystals with translational symmetry in a more fundamental way. This book presents the methods of structural analysis of incommensurately modulated crystals and incommensurate composite crystals <...>

This book is intended to be a complete and clear introduction to the field of crystallography for undergraduate and graduate students and lecturers in physics, chemistry, biology, materials and earth sciences, or engineering. It includes an extensive discussion of the 14 Bravais lattices and the reciprocal to them, basic concepts of point group symmetry, the crystal structure of elements and binary compounds, and much more. Besides that, the reader can find up-to-date values for the lattice constants of most elements and about 650 binary compounds (half of them containing rare earth metals). The entire notation in this book is consistent with the International Tables for Crystallography. <...>

Развитие ряда разделов современных естественных наук, в их числе физики твердого тела, радиотехники, электроники и оптики, существенно зависит от создания материалов с заранее если не заданными, то планируемыми свойствами. Среди этих материалов видное место занимают окисные соединения, кристаллизующиеся в структурном типе граната.

Many materials are polycrystalline aggregates of tiny crystallites or grains of various sizes and shapes. Even for aggregates whose crystallites are chemically identical, the crystal lattices of the grains will still differ in their orientation in space. Since each crystallite is anisotropic in its physical properties, the macroscopic properties of a polycrystal will likewise be anisotropic unless the orientations of its constituent crystallites are completely random and the anisotropies of the crystallites even themselves out.