出典:Wikipedia
出典:『Wikipedia』 (2010/06/10 16:14 UTC 版)
In crystallography, a fractional coordinate system is a coordinate system in which the edges of the unit cell are used as the basis vectors to describe the positions of atomic nuclei. The unit cell is a parallelepiped defined by the lengths of its edges a, b, c and angles between them α, β, γ as shown in the figure below.