egységsejteknek

In crystallography, an egységsejt, also known as a unit cell, is the smallest repeating structural unit of a crystal lattice. It is a parallelepiped that, when translated in three dimensions, fills all of space to form the entire crystal. The dimensions and angles of the unit cell, along with the positions of atoms within it, define the crystal's structure. There are fourteen unique types of unit cells, classified into seven crystal systems based on their symmetry. These systems are cubic, tetragonal, orthorhombic, monoclinic, triclinic, hexagonal, and rhombohedral (trigonal). Each crystal system has a specific set of constraints on the lengths of the unit cell edges (a, b, c) and the angles between them (alpha, beta, gamma). For example, in the cubic system, all edges are equal in length (a = b = c) and all angles are 90 degrees (alpha = beta = gamma = 90°). The internal arrangement of atoms or molecules within the unit cell, known as the basis, is then replicated through translation of the unit cell to generate the macroscopic crystal. Understanding the unit cell is fundamental to characterizing and predicting the physical and chemical properties of crystalline materials, as these properties are directly related to the arrangement of atoms within the unit cell.