This blog is for educators, academicians, students and those who are interasted to integrate technology in class room.

Crystals shape our world

© IUCr and Wikimedia Commons.
The crystal structure of graphite (bottom) is very different from that of diamond although both are pure carbon.

Crystals —familiar to all in gemstones, glittering snowflakes or grains of salt— are everywhere in nature. Throughout history, people have been fascinated by their beauty and mystery. Two thousand years ago, the process of crystallizing sugar and salt was already known to the ancient Indian and Chinese civilizations. Since then, the study of crystals’ inner structure and properties has known steady progress, giving us our deepest insights into the arrangement of atoms in the solid state and leading to advancements the sciences of solid-state physics, chemistry, biology, medicine and even mathematics, by considering the symmetries behind crystalline and quasicrystalline patterns.

In the early 20th century, it was discovered that X-rays could be used to ‘see’ the structure of matter in a non-intrusive manner, thus beginning the dawn of modern crystallography —the science that examines the arrangement of atoms in solids. X-ray crystallography has allowed us to study the chemical bonds which draw one atom to another. Crystallographers now apply this knowledge to modify a structure and thus change its properties and behavior. Since this discovery, crystallography has become the very core of structural science, revealing the structure of DNA, allowing us to understand and fabricate computer memories, showing us how proteins are created in cells and helping scientists to design powerful new materials and drugs. Thus crystallography has many applications. It permeates our daily lives and forms the backbone of industries which are increasingly reliant on knowledge generation to develop new products, in widely diverse fields that include agro-food, aeronautics, automobiles, cosmetics and computers as well as the electro-mechanical, pharmaceutical and mining industries.

Image: Wikimedia.
Snowflakes are crystals. Their hexagonal symmetry results from the way in which water molecules are bound to each other.

Although crystallography underpins all of the sciences today, it remains relatively unknown to the general public. That is one of the reasons why the United Nations General Assembly (UNGA) proclaimed 2014 as the International Year of Crystallography (IYCr2014)*, and requested UNESCO to lead and coordinate, with the International Union of Crystallography (IUCr), the planning and implementation of educational and capacity-building activities during the Year.

2014 marks the centennial of the birth of X-ray crystallography, thanks to the work of William Henry, William Lawrence Bragg (father and son) and Max von Laue —the later was awarded the 1914 Nobel Prize in Physics for his discovery of the diffraction of X-rays by crystals.

A century later, the International Year of Crystallography 2014 highlights the continuing importance of crystallography and its role in addressing post-2015 development issues such as food security, safe drinking water, health care, sustainable energy and environmental remediation; as well as commemorating auspicious crystallography accolades. This Year also commemorates the 50th anniversary of another Nobel Prize, awarded to Dorothy Hodgkin for her work on vitamin B12 and penicillin, and is the 400th anniversary of Kepler’s observation of the symmetrical form of ice crystals (in 1611), thus beginning the wider study of the role of symmetry in matter.

* At its sixty-sixth session in July 2012

Main objectives

© Shutterstock/S_E.
Crystallography can identify new materials that purify water, such as nanosponges
  • Increasing public awareness of the science of crystallography and how it underpins most technological developments in our modern society
  • Inspiring young people through public exhibitions, conferences and hands-on demonstrations in schools
  • Illustrating the universality of science
  • Supporting the Africa Initiative on Crystallography and creating similar programmes in Asia and Latin America
  • Fostering international collaboration between scientists worldwide, especially North–South contributions
  • Promoting education and research in crystallography and its links to other sciences
  • Involving the large synchrotron and neutron radiation facilities worldwide in the celebrations of IYCr2014, including the SESAME project set up under UNESCO auspices

Main activities

Phillip Maiwald/Wikipedia.
Lotfollah Mosque in Iran.
  • Organizing hands-on Crystallography Open Laboratories
  • Encouraging the organization of Crystal Growth competitions worldwide
  • Fostering the organization of Crystallography Exhibitions
  • Launching an open-access crystallography journal
  • Providing all levels of students, from pre-school to university, with crystallography demonstrations at appropriate levels
  • Publicizing the contributions that crystallographers make to the global economy by submitting articles to the press and to magazines or developing television and radio programmes
  • Sponsoring poster exhibitions highlighting the usefulness and wonders of crystallography
  • Organizing problem-solving projects through which students can use their knowledge of crystallography, physics and chemistry
  • Publicizing the contributions that crystallography has made to improve lives, particularly recent developments in drug design and material science
  • Organizing crystal-growing competitions
  • Interacting with governments to underscore the importance of a strong crystallographic education
  • Organizing consultations concerning the best ways to save all diffraction data collected in large-scale facilities and crystallography laboratories

Key events

© IUCr.
Antibodies binding to a virus.
  • Opening Ceremony of the IYCr204, UNESCO Headquarters, 20-21 January 2014
  • Open Laboratories in Crystallography, in Africa, Asia and Latin America, during the Year
  • Asian Summit Meeting on Crystallography, Karachi, Pakistan, 28-30 April 2014
  • Latin America and Caribbean Summit Meeting on Crystallography, Campina, Brazil, September 2014
  • African Summit Meeting on Crystallography, Bloemfontein, South Africa, 15-17 October 2014.


IYCr2014: What crystallography can do for you

The aim of this short video is to announce 2014 as the International Year of Crystallography. Crystallography is that branch of science that is concerned with the investigation of the arrangement of atoms in matter. It is from the basic knowledge of how atoms are linked to each other to form molecules or extended structures that the properties and behaviour of materials can be understood. Crystallography is thus vital in chemistry, biology, physics, materials science, mineralogy, and other disciplines. Hence the title of the video: IYCr2014: What crystallography can do for you. Our commitment for 2014 is to tell the world about the enormous contribution that crystallography makes to society.
The video begins with a view of the beautiful Pulpí geode in Almería in southern Spain, Europe’s largest geode. The walls of this ovoid cave, which measures approximately 8 x 2 x 2 metres, are coated with huge transparent  gypsum crystals.These crystals resemble large blocks of ice, bringing to mind the Greek origin of the word crystal: krystallos, meaning supercooled water. The cave is a magnificent example of the aesthetics of the crystalline world.
From the very moment we get up, and with every step we take, there are crystals all around us. We find crystals as components of our toothpaste, as sugar grains or forming the structure  of an eggshell, thus controlling its mechanical properties. Crystals are also in the liquid crystal displays of alarm clocks, our mobile  phones and our computer screens. Crystals are also in the catalytic converters found in cars, in the snow falling outside or in the frozen foods in our freezer. Crystals are literally everywhere in our daily lives.
Our bones as well as our teeth are made of crystals of a type of calcium phosphate, called hydroxylapatite, which forms our skeleton, allowing us to stay upright. Single crystals of calcite (one of the most common minerals) located in the inner ear control our equilibrium. We do not fall down because of crystals! Advances in the discipline of crystallography help to produce not only biocompatible materials mimicking the size and texture of these hydroxylapatite crystals for better prostheses but also new materials inspired by crystal structures that are part of living organisms, such as snail shells, coral or pearls.
The vast majority of the minerals that make up rocks are crystals. Snowflakes themselves are nothing but crystallized water. In many cases these natural mineral crystals display beautiful polyhedral shapes with sharp edges that tell us about the internal ordered structure characteristic of crystalline matter. Jewels and semiprecious  stones appear mostly as crystallized minerals in nature. Furthermore, the study of the properties of natural crystals improves extraction and processing in modern mining.
The vast majority of today’s materials such as semiconductors, superconductors, light alloys, non-linear optical elements and catalysts are crystalline, as are materials that are expected to play a role in our future, for example quasicrystals and graphene.
New technologies use liquid crystals for watches and telephones, crystals for lasers, semiconductors in the electronic components of chips and LED displays.
Every medicine needs to be crystallized to ensure its purity, verify its pharmacological functionality and improve its efficiency. Thanks to crystallography there are new methods that allow us to visualize the spatial arrangement of atoms and molecules and use this knowledge to understand how drugs work and how they can be improved.
Conserving precious works of art is a continuing problem because of the materials used. Modern crystallographic techniques allow us to identify these materials and understand the reactions that cause the material to age.
Crystals and crystallographic theories play a fundamental role in art and beauty. For instance, the periodic  repetition of matter that constitutes crystals creates patterns that are similar to those found in the mosaics of the Alhambra and even today helps to inspire new decorative designs.The concept  of crystal and crystalline order and the rationale behind it has always fostered an appreciation towards the natural harmony and beauty of the science, which is clearly shown in some of M. C. Escher’s prints in architecture and philosophy. Purist and cubist art as well as the architectural dreams of Le Corbusier that we can see today on the skylines of our cities have been inspired by crystals.
We all know that the most valuable gemstones are crystalline, like diamonds, rubies and emeralds …
… but few people know that the cosmetics industry exploits the properties of crystals: colour and texture depend on the shape and size of the crystalline phase used in the manufacture of beauty products.
We are all familiar with sugar and salt, both of which are crystals. The quality and taste of brown and white sugar depend on how they are crystallized. The prices are different for simple table salt, Maldon salt or “fleur de sel” because they are crystallized in different ways. But you may be surprised to learn that chocolate also contains crystals and that the quality of the chocolate is dependent on how these cocoa fatty acid crystals crystallize. The taste and quality of ice cream depends on the size and shape of the ice crystals it contains.
Crystalline pigments add colour to our lives. But surprisingly it is the interference of light  with the crystal structure of chitin rather than pigments that gives butterfly wings or birds’ feathers their beautiful colours. The exploitation of so-called “structural colours” may play a role in the future of the design industry.
The crystallization of fertilizers, soil conditioners and other agrochemicals must be performed to higher degrees of accuracy now new quality-control measures are in effect.
Solar photovoltaic panels use crystalline silicon to convert sunlight into electricity. The future of solar energy depends on developing new arrangements of crystals in semiconductors. Zeolites, highly porous crystalline materials, are used in petroleum refinement to obtain better and cleaner fuel.
Crystals that form some types of meteorites contain information about the history of the early stages of our planet and solar system.
Revealing the mineral composition of Mars, the Moon and outer space is the first step to knowing about the places we may be destined to explore and live. Data on mineral composition is also crucial in answering the age-old question: is there life on other planets? Crystallography provides the technology to characterize the mineral composition and share some of the secrets of other planets and solar systems.
Currently we do not have microscopes powerful enough to observe the intimate structures of materials. Thanks to developments in diffraction theory and the ability to crystallize large and complex biological macromolecules, crystallographers are able to reveal the atomic structure of nucleic acids and proteins.Thus we are able to understand the relationships between atomic structure and biochemical function of these key molecules, i.e. how life works at the molecular  level.
Thanks to these crystallographic methods, crystallographers have revealed the helical structure of DNA, how haemoglobin transports oxygen and how the hormone insulin  works. And it is crystallography and crystallographic techniques that have shed light on the structure of the target protein involved in AIDS.


The video ends with an animation featuring the two great discoveries on which crystallography is built. The first discovery, in the 19th century, is that a crystal is made up of the periodical arrangement of units of matter (either atoms, molecules or macromolecules) and that, as a result of this internal periodical order, crystals display external polyhedral shapes with precise symmetry. The second landmark discovery in the early years of the 20th century is that the interaction of crystals with a beam of X-rays produces diffraction patterns that contain valuable information about the internal structure of the crystals. Crystallographers have been able to develop theoretical and experimental tools to deconstruct these sets of spots and transform them into images of the atoms and molecules from many types of materials, from common table salt or the most healing medicines to the complex constituents of life: nucleic acids, viruses and proteins. And with that critical information, crucial advances in medicine, materials engineering, chemistry, geology and pharmacology have contributed to and continue to improve social welfare. No wonder  then that the Nobel Committee has awarded the discipline 28 Nobel Prizes.


Learn about crystallography

These pages link to information about the subject of crystallography.




MOOC on “The Fascination of Crystals and Symmetry”


Beauty and Structure

Glistening rubies, sugar, stones or snowflakes – we encounter crystals in our daily lives. Even though they all look very different, there is one thing they have in common: their molecules are arranged in lattices. How do these structures form? What properties do they contribute to these materials? How can you classify them? This is shown in this course. The focus is placed upon the creation of a crystallographic basis, enabling you to decipher and understand the cryptic language and the abstract concepts of crystallography. With this basis, you will be prepared for the advanced lectures and readings in solid state chemistry and physics, material sciences, crystallography or mineralogy.­

Aesthetics and Fundamentals

After the definition of the term “structure” and the notion of what makes a crystal and why anisotropic properties (specific materials properties are direction dependent) result from this, the correspondence principle (relationship between the inner structure and the outer shape of the crystal) is introduced and visualized in aesthetic images. We will treat the concept of the unit cell – the fundamental building block of every crystal – in detail. We want to use platforms like flickr or twitter to share everyday life examples with each other; thereby the concepts of translation lattices and motives are taught. In this context, there will be enough challenging exercises to train and apply what has been learned so far. Another unit will cover the hierarchical systematics in the classification of crystals (crystal systems, crystal classes, Bravais lattices) and its benefits. Occasional excursus will be used to link course content to current events and questions in research (i.e. the International Year of Crystallography or 2011’s Nobel Prize in chemistry for the discovery of quasicrystals).

Explore Crystals in 3D

Next, the symmetry of crystals is dealt with. All macroscopic and microscopic symmetry elements and symmetry operations (mirror planes, glide planes, centers of inversion, rotational axes and screw axes) are characterized and illustrated with many examples gathered through crowdsourcing. We hope that you will take many pictures, we can discuss together regarding symmetry elements. Finally, the connection to the systematics of crystals is shown and we will discuss the concept of what is called “space group”. The last part of the course will focus on practical experience. Using free computer programs for three-dimensional crystal visualization (Mercury, VESTA etc.), you are given the opportunity to discover countless crystal structures, which are freely available on the internet as CIF-files. Concepts like the asymmetric unit, fractional coordinates, general and special positions, multiplicity and Wyckoff positions can be discovered, developed and understood on the fly. Of course, the respective tutorials to use the software will be provided.

Learning targets / Educational objectives

Upon completion of this online course you can answer the following questions:

What do the patterns on wallpapers and the structures of crystals have in common? There are innumerable appearances of crystals. How can all crystals in this world be classified into seven different crystal systems? Why is it sufficient to know the positions of only a few atoms to precisely describe a crystalline solid consisting of a myriad of atoms? How can you find crystallographic data and how can it be analyzed regarding symmetry? What relationship exists between the structure and the properties of a material? Why is diamond so hard and how can you explain phenomena such as ferroelectricity?

Prior Knowledge

Basic knowledge in chemistry (atoms, simple molecules).


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