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14 Bravais space point latticesabc
abccrystal systemsisometric (cubic), tetragonalorthorhombicmonoclinictriclinic,hexagonal systemshexagonal division or system and the trigonal (rhombohedral) division or system
ssss1 The six crystal systems and 32 crystal classes, with their characteristic symmetry and crystal forms.
System Crystal class Class symmetry Total symmetry Isometric Hexoctahedral
4
2 Hextetrahedral
3 Gyroidal 432 432 Diploidal
2
Tetaroidal 23 23 Tetragonal Ditetragonal–dipyramidal 4/m2/m2/m 42 Tetragonal–scalenohedral
2 Ditetragonal–pyramidal 4mm 4 Tetragonal–trapezohedral 422 42 Tetragonal–dipyramidal 4/m 4 Tetragonal–disphenoidal
Tetragonal–pyramidal 4 4 Hexagonal(hexagonal) Dihexagonal–dipyramidal 6/m2/m2/m 62 Ditrigonal–dipyramidal 6m2 62 Dihexagonal–pyramidal 6mm 6 Hexagonal–trapezohedral 622 62 Hexagonal–dipyramidal 6/m 6 Trigonal–dipyramidal
Hexagonal–pyramidal 6 6 Hexagonal (rhombohedral or trigonal) Hexagonal–scalenohedral
2 Ditrigonal–pyramidal 3m 3 Trigonal–trapezohedral 32 32 Rhombohedral
Trigonal–pyramidal 3 3 Orthorhombic Rhombic–dipyramidal 2/m2/m2/m 2 Rhombic–pyramidal mm2 2 Rhombic–disphenoidal 222 2 Monoclinic Prismatic 2/m 2 Sphenoidal 2 2 Domatic m 1m Triclinic Pinacoidal
i Pedial 1 None
ssss1 Relationship between (a) atomic packing, (b) a unit cell, and (c) octahedral coordination polyhedra in halite (NaCl).
