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by

SID

efects in Solids

Solid State

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Defects in Solids

Point Defects

Line Defects

Stoichiometric Defects

NonStoichiometric Defects

Impurity Defects

Frenkel Defects

Schottky Defects

Metal Excess Defects

Metal Deficiency Defects

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Point Defects

Point Defects

Line Defects

Stoichiometric Defects

NonStoichiometric

Defects

Impurity Defects

Frenkel Defects

Schottky Defects

Metal Excess Defects

Metal Deficiency

Defects

Point defects are where an atom ismissing or is in an irregular place in the

lattice structure.

Point defects are defects that occur only

at or around a single lattice point.

There are three types of point defects.

They are :- Stoichiometric Defects

Non-Stoichiometric Defects

Impurity Defects

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Line Defects

SECTION TITLE

Point Defects

Line Defects

NonStoichiometric

Defects

Impurity Defects

Frenkel Defects

Schottky Defects

Metal Excess Defects

Metal Deficiency

Defects

Line defects are where a sequence orcomplete line of atoms are missing in

the lattice structure.

Line defects are defects that occur over

a long/large area in the crystal lattice

structure.

Stoichiometric Defects

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Stoichiometric Defects

SECTION TITLE

Point Defects

Line Defects

NonStoichiometric

Defects

Impurity Defects

Frenkel Defects

Schottky Defects

Metal Excess Defects

Metal Deficiency

Defects

Stoichiometric defects are the defects

that do not cause to change the

stoichiometric ratio/proportion of the

elements in the chemical compound or

the molecule.

Stoichiometric defects are of two types.

They are :

Frenkel Defects

Schottky Defects

Stoichiometric Defects

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Non-Stoichiometric Defects

SECTION TITLE

Point Defects

Line Defects

NonStoichiometric

Defects

Impurity Defects

Frenkel Defects

Schottky Defects

Metal Excess Defects

Metal Deficiency

Defects

Stoichiometric Defects

Non-stoichiometric defects are thedefects that cause to change the

stoichiometric ratio/proportion of the

elements in the chemical compound or

the molecule.

Non-stoichiometric defects are of two

types. They are :

Metal Excess Defect Metal Deficiency Defect

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Impurity Defects

SECTION TITLE

Point Defects

Line Defects

NonStoichiometric

Defects

Impurity Defects

Frenkel Defects

Schottky Defects

Metal Excess Defects

Metal Deficiency

Defects

Stoichiometric Defects

Impurity defects are defects that arise dueto the presence of extra / foreign elements

in the crystal structure of a compound that

are not present in the chemical formula of

the compound.

Example : +2ions present in the crystal

structure of NaCl even when the element

Sr has no presence in the NaCl molecule.

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Frenkel Defects

SECTION TITLE

Point Defects

Line Defects

NonStoichiometric

Defects

Impurity Defects

Frenkel Defects

Schottky Defects

Metal Excess Defects

Metal Deficiency

Defects

Stoichiometric Defects

Frenkel defects are the defects that arecaused when one cation(+ve charge ion)

leaves its original position (also called as its

lattice point) and occupies any gap

(interstitial site) within its crystal structure.

This kind of defect is observed/seen in case

of solids where the size difference

between the cation (+vely charged ion) and

anion (-vely charged ion) is high and incase of solids where the co-ordination

number of the atoms is low.

The density of the crystal does not change

due to the occurrence of this defect.

Due to Frenkel Defects there exists holes in

the crystal structure.

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Schottky Defects

SECTION TITLE

Point Defects

Line Defects

NonStoichiometric

Defects

Impurity Defects

Frenkel Defects

Schottky Defects

Metal Excess Defects

Metal Deficiency

Defects

Stoichiometric Defects

Schottky defects are the defects that arecaused due to the missing of a pair of

cation and anion from the crystal

structure.

Due to this defect the density of the

crystal structure decreases.

This defect is seen in solids where the

cation and anion are almost equalin size

and also in solids where the co-ordinationnumber of each atom is high.

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Metal Excess Defect

SECTION TITLE

Point Defects

Line Defects

NonStoichiometric

Defects

Impurity Defects

Frenkel Defects

Schottky Defects

Metal Excess Defects

Metal Deficiency

Defects

Stoichiometric Defects

Metal excess defect means the defectthat rises due to excess % of metal

present in the crystal structure.

There are 2 types of metal excess

defects. They are:

DUE TO EXCESS CATIONS

In this kind of defect extra cations and

associated number electrons arepresent in crystal structure.

DUE TO ANION VACANCY

In this kind of defect the anions in the

crystal are absent from their lattice

points. To compensate for the

electrical neutrality equivalent number

of electrons are filled with in the

crystal.

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Metal Deficiency Defects

SECTION TITLE

Point Defects

Line Defects

NonStoichiometric

Defects

Impurity Defects

Frenkel Defects

Schottky Defects

Metal Excess Defects

Metal Deficiency

Defects

Stoichiometric Defects

Metal deficiency defect means thedefect that rises due to less % of metal

present in the crystal structure.

There is 1 type of metal excess defects.

That is :

DUE TO MISSING CATION

In this kind of defect the cation in the

crystal are absent from their lattice

points. To compensate for the

electrical neutrality the metal ions that

are present in the crystal jump to a

higher oxidation state.

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