point defects in crystals

Defects in Crystals - According to third law of thermodynamic it is only at OK that true crystals passes perfect order of arrangement of atoms in pure crystals. But with rise in temperature some derivations from complete order takes place. Presence of impurit..

Types of defects in Crystals - The defect, which arises due to the irregularity in the arrangement of atoms or ions are called point defects. Point defects are of three types: Stoichiometric defects Non-stoichiometric h..

The defect, which arises due to the irregularity in the arrangement of atoms or ions are called point defects. Point defects are of three types: Stoichiometric defects Non-stoichiometric defects Impurity defects..

When the crystals are unstable, they are gently pressed between the folds of filter papers, and are finally placed in a vacuum desiccator to obtain dry crystals. If the substance is stable and has a high melting point, the crystals are pressed between the fo..

In covalent crystals, the constituent particles are atoms of the same or different kind, which are bonded to one another by a network of covalent bonds. The important characteristics of covalent crystals are: The covalent crystals are incompressible and hard. The..

If imperfections in the crystal are such that the ratio between the anions and cations remain same as represented by the molecular formula, the defect is called a stoichiometric defect..

If imperfections in the crystal are such that the ratio between the anions and cations remain same as represented by the molecular formula, the defect is called a stoichiometric defect. There are three types of stoichiometric defects: Schottky defect Fre..

Calculation of Number of Particles per Unit Cell of a Cubic Crystal System - Calculation of Number of Particles per Unit Cell of a Cubic Crystal System. Keeping the following points in mind we can calculate the number of atoms in a unit cell. An atom at the corner is s..

Crystal Field Splitting in Tetrahedral Complexes - The tetrahedral arrangement of four ligands surrounding the metal ions is as shown in the figure. fig 10.2 - Tetrahedral arrangement of four ligands surrounding the metal ions It is clear from the figure that none of the d-orbitals p..

Group 13 elements such as Ga and Al and group 15 elements such as P and As can enter the crystal structure of group 14 elements Ge or Si substitutionally. Group 15 elements have one excess valence electron as compared to Group 14 elements (Si or Ge). Therefore after forming four covalent..