Chemical structure refers to the spatial arrangement of atoms in a molecule and the chemical bonds that hold the atoms together. Chemical structure can range from the very simple, such as diatomic oxygen or nitrogen molecules, to the very complex, such as protein or DNA molecules. Chemical structure can be represented using a structural formula. A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... The structure of part of a DNA double helix. ... The structural formula of a chemical compound is a graphical representation of the molecular structure showing how the atoms are arranged. ...
A common method for determining chemical structure is X-ray diffraction. X-ray crystallography is a technique in crystallography in which the pattern produced by the diffraction of x-rays through the closely spaced lattice of atoms in a crystal is recorded and then analyzed to reveal the nature of that lattice. ...
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Molecular coordinates and other types of chemical information are stored in a large number of formats, and originate from sources such as several crystallographic databases, nmr and other spectroscopic techniques, quantum chemistry calculations (see here for the first video animations for a chemical paper mounted on a gopher server), molecular mechanics or dynamics runs.
In our chemical MIME (Multipurpose Internet Mail Extension) proposal, we have identified a number of well defined formats and proposed their use as chemical MIME types.