Crystal defects active dissolution, energy

Active Dissolution and Crystal Defects—Energy Considerations... 

Wherever there is a defect in a crystal lattice, interatomic forces will remain unbalanced and the free energy will be less negative than elsewhere in the crystal, although generally the lattice will deform locally to smooth this out. Nevertheless, defect sites (especially of the extended variety) tend to be more chemically reactive than the bulk crystal and tend to be active sites for crystal growth, dissolution, corrosion, and catalytic activity. 

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