By definition crystal is a periodic arrangement of repeating “motifs”( e.g. atoms, ions). The symmetry of a periodic pattern of repeated motifs is the total set of symmetry operations allowed by that pattern

In Unit 1 Crystal Properties of this course, you have been introduced to the parts of crystal, crystal forms and representation of crystal face. Further in Unit 2 Crystal Symmetry, you have learnt about laws of …

Crystal Systems There are 7 crystals systems and they are named: Triclinic, Monoclinic, Orthorhombic, Tetragonal, Trigonal, Hexagonal, and Cubic. What differentiates one crystal system from another? The …

Do not assume the metric relations indicate the correct point group and crystal system!!!

In the crystalline solid state, periodicity is described by a three-dimensional repeat unit known as a unit cell. Although the unit cell for each crystalline material may be unique to that substance, unit cells can …

Classification of Crystal Structures All crystal structures can be categorized into 7 unique crystal systems based on lattice parameters ( a, b, c and angles α, β, γ).

A crystal's lattice is a three dimensional network of atoms that are arranged in a symmetrical pattern. Each crystal system consists of a set of three crystallographic axes (a,b, andc) in a particular …