Symmetry groups {orthorhombic symmetry group} can have rotation by 180 degrees and reflection. Crystals {orthorhombic crystal} can have three two-fold axes, which are all perpendicular but have different lengths, to make three crystal classes.
Physical Sciences>Chemistry>Inorganic>Phase>Phases>Solid>Crystal>Symmetry
5-Chemistry-Inorganic-Phase-Phases-Solid-Crystal-Symmetry
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Date Modified: 2022.0224