Identify three crystal point defects. - Leaving Cert Engineering - Question 1 - 2010

Vacant Site Defect: This occurs when an atom site in the crystal lattice is unoccupied. The absence of an atom creates a point defect that can influence the material properties.

Substitution Defect: This defect arises when an atom in the lattice is replaced by a different atom. This can happen in alloys where one metal atom substitutes for another in the crystal structure.

Interstitial Defect: This defect is created when extra atoms are positioned in the lattice at non-regular sites. These interstitial atoms can lead to distortion in the lattice structure.