Question

what do you mean by point defect in a crystal?​

Answer 1

an imperfection in a crystal's lattice structure, either a missing atom or ion creating a vacancy in the lattice or an extra atom or ion between two normal lattice points creating an interstitial...

Answer 2

Answer:

Point defects are where an atom is missing or is in an irregular place in the lattice structure. Point defects include self interstitial atoms, interstitial impurity atoms, substitutional atoms and vacancies. A self interstitial atom is an extra atom that has crowded its way into an interstitial void in the crystal structure. Self interstitial atoms occur only in low concentrations in metals because they distort and highly stress the tightly packed lattice structure.

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