X-ray crystallography, the use of X-ray diffraction to determine the structure of crystals or molecules, such as nucleic acids. ... X-rays are diffracted by the electrons in the molecules and if molecular crystals of a compound are used, the electron density distribution in the molecule can be determined. Many of the medicinal chemicals that have been discovered by scientists are very difficult to produce naturally in large amounts. Other researchers have used X-ray technologies to record the structures of proteins, haemoglobin, and the double-helix of DNA structure (deoxyribonucleic acid). X-ray crystallography was initially used to investigate the structure of minerals, confirming and refining the crystallographic descriptions. Use of the technique was expanded to the investigation of metals, alloys, and inorganic and organic chemical substances. More recently, biomedical research has utilized the technique for the investigation of the structure and dynamics of proteins, nucleic acids, and other biological molecules. Research into microelectronics and semiconductors, as well as pharmaceutical research, continue to rely on the qualities of x-ray crystallography.
