More mechanisms for alloy ordering

Ordering affects many properties of the material but primarily modifies the energy band structure. This has direct and measurable consequences for the optical pro- 

Zincblende alloy with CuAu ordering CuPt ordering 

It is important to emphasize again that this is not normally an equilibrium structure in the bulk of the solid. Calculations show that a random bulk alloy is typically favored over the CuPt or CuAu organization. Ordering of this type in alloys is a result of the growth process and is directly tied to the surface structure as growth occurs. This is why sometimes one order is found, sometimes another, and sometimes no order is present. 

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