First published diffraction pattern of a crystal of Zinc blend obtained by  W. Friedrich, P. Knipping and M. Laue ( 1912). The 3-fold symmetry of the pattern is a reflection of the symmetrical arrangement of the atoms inside the crystal. From the arrangement of the spots and their relative intensities the geometric disposition of the atoms in the crystal can be deduced: their Cartesian coordinates (x,y,z) in 3D.

As the year 2014 approaches, more and more institutions all over the world prepare to celebrate the International Year of Crystallography  (IYCr2014) with all kinds of activities and media to communicate to the lay public the importance of this obscure science.  Crystallography is an arcane science to the majority of the world population; yet, its theory and findings are the basics for the atomic knowledge of the world that surrounds us. The combination of crystals and X-rays in the physical phenomenon call ‘diffraction’ permit the unveiling of the atomic structure inside the crystals. This was the key insight of the Braggs (W. Henry and W. Lawrence, father and son) in 1913 when they discovered the arrangement of the atoms in the common salt (Sodium Chloride, NaCl).

May this brief note serve as the introduction to the excellent material (video, audio, photographs, interviews etc.) released by the Royal Institution in London to commemorate this event. I just encourage you to access this site and pick and choose whatever piques your curiosity and you will be amply rewarded.

http://www.richannel.org/celebrating-crystallography/

I could not write any better summary of the beauty of crystallography and of its impact in our world today and in the future. Previous and future postings on this site elaborate on the many different aspects of the science of crystallography. From its mathematical underpinnings on group theory to the physics of diffraction theory and Fourier Transforms, to the intricate atomic description of the structure of the molecules that are now being unveiled by modern crystallographers.

I wish you an insightful and enjoyable journey.