
July 30, 2015 13:48 PSP Book - 9in x 6in 03-Nanomagnetism-c03
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Alloy Thin Films and Nanostructures
Figure 3.3 (a) The disordered face-centered cubic (fcc) unit cell and the (b)
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ordered face-centered tetragonal (fct) structure.
the Fe and Pt atoms on alternating atomic planes along the c axis
or (001) direction. This segregation causes a lattice distortion and
hence a change from an fcc unit cell in which all sides are equal
(a = b = c)toanfct structure in which the c axis contracts and
the a axis expands (a = b = c), thus resulting in a c/a ratio less
than unity. The lattice parameters and c/a ratios for select bulk L1
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ordered alloys are tabulated ...