Difference between Metal excess and metal deficient defects
Difference between Metal excess defect and metal deficient defects are in tabular form below.
Metal excess Defect |
Metal deficiency defect |
1) A metal excess defect is a type of crystal defect that occurs in crystal lattices. Either an anionic vacancy or an extra Cation cause these defects. | Metal Deficiency Defects is a type of crystal defect that occurs in crystal lattices in which either a cation vacancy or an extra anion causes the defects. |
2) Metal Excess defects is caused by the anionic vacancies and by extra cation in the interstitial sites. | Metal deficiency defects are caused by the cationic vacancies and by the extra anion in the interstitial sites. |
3) Metal excess defect is when the anion escapes from the lattice and forms a bond with atmospheric cation. | Metal deficiency defects arise when cation itself is surrounded by a sea of anion. |
4) Examples: Cl- forming bonds in the atmosphere where Na+ is present this causes an electron to be shifted to the centre and all metal surrounded to the electron. | Example: in Feo there is a tendency of Fe2+ to change to Fe3+ due to oxidation so in order for this to happens, some of this positive charge is lost, hence, metal is deficient |
5) There are two different types of metal excess defects that are metal excess defects due to anionic vacancy and metal excess defect due to extra cations. | These are two different type of metal deficiency defects that is that is metal deficiency defect due to presence of extra cations. |
6) Metal defect Due to anionic vacancy the loss of negative ions from the lattice sites, which leave behind a hole that is occupied by an electron in order to maintain the electric balance of the crystal lattice. | Metal deficiency defects due cation varancies, a cation is missing from its lattice site therefore, the extra negative charged is balanced by getting two charged insted of one charged. |
7) These cations tend to occupy the interstitial sides of the crystal lattice, along with the cation formation the released electrons go to the neighboring interstitial sites.
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Metal deficiency defects due to presence of extra cation. |
8) Examples: of a metal excess defect are sodium chloride, potassium chloride, zinc oxide etc. | Extra anions occur on the interstitial sites and the adjacent ion at another interstitial sites help to maintain the electrical neurallity of the lattice.Example: Of a metal deficiency defect is nickel oxide. |