# Crystallography

Crystallography is the experimental science of determining the arrangement of atoms in crystalline solids.

## Quotes

* In my own field, x-ray crystallography, we used to work out the structure of minerals by various dodges which we never bothered to write down, we just used them. Then Linus Pauling came along to the laboratory, saw what we were doing and wrote out what we now call Pauling's Rules. We had all been using Pauling's Rules for about three or four years before Pauling told us what the rules were.
** John Desmond Bernal in: John Desmond Bernal A History of Classical Physics: From Antiquity to the Quantum, Barnes & Noble Publishing, 1997, p. 116
* ...all the work of the crystallographers serves only to demonstrate that there is only variety everywhere they suppose uniformity...that innature there is nothing absolute, nothing perfectly regular.
** Leclerc, Georges Comte de Buffon. Histoire Naturelle des Mineraux, Volume III
* I miss the old days, when nearly every problem in X-ray crystallography was a puzzle that could be solved only by much thinking.
** Pauling, Linus. "X-Ray Crystallography and the Nature of the Chemical Bond"

### Crystallography needs a governing body

Paolo G. Radaelli In: Crystallography needs a governing body, Instituto de Química Física Rocasolano (xtal.iqfr.csic.es)
* Since modern crystallography dawned with X-ray diffraction experiments on crystals by Max von Laue in 1912 and William and Lawrence Bragg (a father and son team) in 1913, and was recognized by Nobel prizes in physics for von Laue in 1914 and the Braggs in 1915, the discipline has informed almost every branch of the natural sciences.
* Aeroplanes fly safely because crystallography tests computer models of materials under stress. Drugs are more potent because crystallographers can see and modify how molecules interact with target sites in cells. An X-ray diffraction instrument on NASA’s Curiosity rover is now even studying the mineralogy of Mars.
* Crystallography is increasingly focusing its resources on large multidisciplinary facilities, such as powerful X-ray and neutron sources.
* Crystallographers have a raft of methods at their disposal. Von Laue scattered X-ray photons from atoms. Now experimenters can also bombard crystal lattices with electrons and neutrons, and exploit properties such as the polarization of photons and neutrons and their interactions with magnetic fields.
* It takes a very special breed of scientist to do this work...it is an area of science in which women dominate.
** Georgina Ferry introducing British crystallographer Judith Howard.

### Nature surveys a century back, looks a century ahead in crystallography

Steven T. Corneliusse in:Nature surveys a century back, looks a century ahead in crystallography, Physics today, February 2014
* Thanks to the methods that [Crystallographers] have devised for investigating crystal structures, an entirely new world has been opened and has already in part been explored with marvelous exactitude. The significance of these methods, and of the results attained by their means, cannot as yet be gauged in its entirety, however imposing its dimensions already appear to be.
** By: William
* Crystallography remains a cutting-edge field, and one that, if harnessed properly, could contribute as much in the next 100 years as it did in the previous 100. The development of the x-ray free-electron laser, for example, is a monumental technical achievement, and one that seems more suited to the world of 2114 than 1914, or even 2014.
* Crystallographers should take a lesson from particle physicists and create a body run by scientists for the governance of large international x-ray and neutron facilities. It should be guided by input from regular meetings of researchers from across the scientific community. This will ensure that the next generation of infrastructure will have the strongest possible scientific case, articulated clearly.
** By: Paolo G. Radaelli
* Researchers hope to be able to get diffraction patterns from individual molecules, allowing them to watch biomolecules moving and interacting in a completely natural setting, surrounded by water, instead of trapped in the artificial environment of a crystal. That’s my future vision for crystallography. Get away from being a coroner imaging dead molecules, and instead get molecular movies.
** By: Fromme on X-ray free-electron laser (XFEL)