Frenkel Defect - Definition, Examples, Formula, FAQs
The meaning of disability is a defect or imperfection. Solid crystals also show certain types of defects that we learn from the chemistry of a solid state. Some crystal units may have one or more atoms under which other units are suitable for crystals. These crystalline imperfections are called defects in crystals. We will discuss in detail Frenkel's shortcomings in this article.
This Story also Contains
- Definition of Frenkel defect:
- What is Frenkel Defect and Give Frenkel defect example:
- In frenkel defect Formula
Definition of Frenkel defect:
When an atom or a small ion (usually a cation) leaves its place in the cell, it creates space and becomes a meeting place by staying close to one another. Thus, space opens up in space. It was discovered by Soviet philosopher Yakov Frenkel. It is a type of error feature also known as a split feature.
What is Frenkel Defect and Give Frenkel defect example:
The following are examples of In frenkel defect -
NaCl (Sodium Chloride) (In frenkel defect shown on NaCl in the photo above)
Sulphide zinc
Silver (I) Chloride
Silver (I) Bromide
Silver (I) Iodide
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Reason for In frenkel defect
When the computer ionic size of the anion is much larger than the cations then In frenkel defect occurs. Due to the size difference in ions, the ion replaces the inner lattice. Ionic crystals with Frenkel defect is also known as to remain naturally neutral. As the number of cations and anions here remains the same. Therefore, it can be said that Frenkel's deformity is indicated by those ionic solids that have significant differences in size between cation and anion.
Frenkel deficiency has no effect on the hardness, size or volume of the crystal as in this ion negative migration occurs within the crystal. Therefore, the density, size and volume of ionic crystals remain the same even if they have a Frenkel feature.
In frenkel defect Formula
The number of Frenkel errors can be calculated according to the formula -
_______
√NN* e-∆H/2πRT
Where N = positions usually reside
N ’= number of positions available
= H = enthalpy issued by 1 In frenkel defect
R = gas constantly
T = heat
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Schottky Defect and In frenkel defect
Schottky's character (a small shooting effect) was named after the famous German scientist Walter H. Schottky, who was awarded the 1936 Royal Society's Hughes Prize for his discovery. In his model, he explains that defects are formed in ionic crystals where ions are illegally charged, leaving their lattice sites leading to job creation. These spaces are designed to continue to keep money neutral in the crystal. The model goes on to explain that the atoms around them move to settle in these spaces. Usually, when defects are found in non-ionic crystals it is referred to as a lattice space element.
The Schottky element is different from the frenkel element, in which atoms permanently leave the crystal in terms of the schottky element, while the atoms usually reside within a stronger crystal than the frenkel element. We will continue to study the features below.
Definition
The Schottky element is a type of defect or imperfection in solid matter caused by a vacuum that is produced by a piece of crystal due to atoms or ions emanating from the inside to the crystal surface.
Other distinctive features of it are;
There is very little difference in size between cation and anion.
Cation and anion both left a solid crystal.
Atoms also come out of the crystal permanently.
Usually, two job vacancies are created.
In terms of the magnitude of the solid state, it decreases significantly.
Examples
It is a type of element in crystals that usually occurs in highly ionic chemicals or in highly synthetic chemicals. The combined lattice has only a slight difference in size between the anions and the cations.
Some typical examples of salts in which Schottky's features are prominent includes Sodium Chloride (i.e NaCl), Potassium Chloride (i.e KCl), Potassium Bromide (i.e.KBr), Cesium Chloride (i.e.CsCl) and Silver Bromide (i.e.).
NCERT Chemistry Notes:
Frenkel Defect
Frenkel's defect is also a crystallographic point error often seen in ionic chemicals. It is named after the Soviet philosopher Yakov Frenkel and differs from the Scottish element in terms of its shape and characteristics. Frenkel degradation usually occurs in ionic chemicals where ions have different sizes.
The point error that occurs when the cation moves to the internal void is called the In-frenkel defect. In this error the cation is removed as it is smaller in size than the anion. AgI, CaF2, NaCl indicate Frenkel error.
This defect does not alter the crystal density.
Normally, in ionic solids, a small ion (called a cation) leaves its place and stays in the space between cells. In this case, a space error will be created in its original location. An internal error can be found in its new state.
Also called separation error.
It occurs when there is a significant difference in the size of the anions and the size of the cations.
Here the density of an object remains unchanged.
An example is AgCl and ZnS.
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