China DOS Union

In 1850, the French crystallographer A. Bravais derived using the method of group theory in mathematics that there are only fourteen space lattices: simple triclinic, simple monoclinic, base-centered monoclinic, simple orthorhombic, base-centered orthorhombic, body-centered orthorhombic, face-centered orthorhombic, simple hexagonal, simple rhombohedral, simple tetragonal, body-centered tetragonal, simple cubic, body-centered cubic, face-centered cubic. According to their symmetry characteristics, they respectively belong to seven crystal systems.

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[ Last edited by zzz19760225 on 2017-11-17 at 14:12 ]