In
X-ray crystallography
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...
, crystallographic disorder describes the
cocrystal
Cocrystals are "solids that are crystalline single phase materials composed of two or more different molecular or ionic compounds generally in a stoichiometric ratio which are neither solvates nor simple salts." A broader definition is that cocryst ...
lization of more than one
rotamer
In chemistry, conformational isomerism is a form of stereoisomerism in which the isomers can be interconverted just by rotations about formally single bonds (refer to figure on single bond rotation). While any two arrangements of atoms in a mole ...
,
conformer
Conformer is a clear acrylic shell fitted after an enucleation if the final artificial eye is not available at the time of surgery to hold the shape of the eye socket and allow the eyelids to blink over the shell without rubbing the suture line.
...
, or
isomer
In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers.
Iso ...
where the center of mass of each form is identical or unresolvable. As a consequence of disorder, the crystallographic solution is the sum of the various forms. In many cases, the components of the disorder are equally abundant, and, in other cases, the weighting coefficients for each component differ. Disorder can entail a pair or several components. Disorder usually arises when the forms are nearly equal in energy and the crystal lattice is sufficiently spacious to accommodate the various components.
File:DOSBIW.png, Structure of Mo(CH3)5 showing 4-fold disorder of one methyl group.[{{cite journal, journal=Chemical Communications, issue=12, title=Pentamethylmolybdenum, authors=Beatrice Roessler, Sven Kleinhenza, Konrad Seppelt, doi=10.1039/b000987n, year=2000, pages=1039–1040]
File:DOSBIWoneRotamer.png, One of four rotamers of Mo(CH3)5.
References
Crystallography
Materials science
Protein structure
Protein methods
Protein imaging
Synchrotron-related techniques