What is "crystallography"

Crystallography \Crys`tal*log"ra*phy\ (kr[i^]s"tal*l[o^]g"r[.a]*f[y^]), n. [Gr. kry`stallos crystal + -graphy: cf. F. cristallographie. See Crystal.]

1. The doctrine or science of crystallization, teaching the system of forms among crystals, their structure, and their methods of formation.

2. A discourse or treatise on crystallization.

n. 1 The experimental science of determining the arrangement of atoms in solids. 2 The study of crystals.

n. the branch of science that studies the formation and structure of crystals

Crystallography is the experimental science of determining the arrangement of atoms in the crystalline solids (see crystal structure). The word "crystallography" derives from the Greek words crystallon "cold drop, frozen drop", with its meaning extending to all solids with some degree of transparency, and grapho "I write". In July 2012, the United Nations recognised the importance of the science of crystallography by proclaiming that 2014 would be the International Year of Crystallography. X-ray crystallography is used to determine the structure of large biomolecules such as proteins.

Before the development of X-ray diffraction crystallography (see below), the study of crystals was based on physical measurements of their geometry. This involved measuring the angles of crystal faces relative to each other and to theoretical reference axes (crystallographic axes), and establishing the symmetry of the crystal in question. This physical measurement is carried out using a goniometer. The position in 3D space of each crystal face is plotted on a stereographic net such as a Wulff net or Lambert net. The pole to each face is plotted on the net. Each point is labelled with its Miller index. The final plot allows the symmetry of the crystal to be established.

Crystallographic methods now depend on analysis of the diffraction patterns of a sample targeted by a beam of some type. X-rays are most commonly used; other beams used include electrons or neutrons. This is facilitated by the wave properties of the particles. Crystallographers often explicitly state the type of beam used, as in the terms X-ray crystallography, neutron diffraction and electron diffraction. These three types of radiation interact with the specimen in different ways.

• X-rays interact with the spatial distribution of electrons in the sample.
• Electrons are charged particles and therefore interact with the total charge distribution of both the atomic nuclei and the electrons of the sample.
• Neutrons are scattered by the atomic nuclei through the strong nuclear forces, but in addition, the magnetic moment of neutrons is non-zero. They are therefore also scattered by magnetic fields. When neutrons are scattered from hydrogen-containing materials, they produce diffraction patterns with high noise levels. However, the material can sometimes be treated to substitute deuterium for hydrogen.

Because of these different forms of interaction, the three types of radiation are suitable for different crystallographic studies.

Crystallography is a book of poetry and prose published in 1994 and revised in 2003 by Canadian author Christian Bök. Based around a that language is a crystallization process, the book includes several forms of poetry including concrete poetry, as well as pseudohistorical texts, diagrams, charts, and English gematria.

Major poems in the book include Geodes and Diamonds.

Bök explains the title in an introduction. Crystallography refers to both the science of crystallography and a reanalysis of the word's roots: crystal meaning "clear", and "graph" meaning "writing".

Inspired by the etymology of the word “crystallography,” such a work represents an act of lucid writing, which uses the language of geological science to misread the poetics of rhetorical language. Such lucid writing does not concern itself with the transparent transmission of a message (so that, ironically, the poetry often seems “opaque”); instead, lucid writing concerns itself with the exploratory examination of its own pattern (in a manner reminiscent of lucid dreaming). (Bök, 2003)