Single Crystal Morphology and its Relationship to Lattice Symmetry

3 SINGLE CRYSTAL MORPHOLOGY AND ITS RELATIONSHIP TO LATTICE SYMMETRY 

A crystal is similar to three-dimensional wallpaper, in that it is an endless repetition of some motif (a group of atoms or molecules). The motif is created by point group operations, while the wallpaper, which we caU the space lattice, is generated by translation of the motif, either with or without rotation or reflection. The symmetry of the motif is the true point group symmetry of the crystal and the S5mmetry of the crystal s external (morphological) form can be no higher than the point symmetry of the lattice. The 

1669 Niels Stensen (1638-1686) - more widely known by his Latinized 

1772 Jean Baptiste Louis Rome de L Isle (1736-1790) publishes his Essai 

1784 French abbe and mineralogist Rene-Just Hauy (1743-1822) 

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