Question

*if we have Body centered* orthorhombicwith unit cell
dimenisons (3,4,6)A , find:

spacing between planes (210)?

Packing fractions?

reciprocal lattice vectors ?

Answer #1

answer : for orthorombic bcc structure we have the packing fraction as

Packing fraction = (2 x 4/3
R^{3} ) / a3 , but R = (3 / 4) a

substituting we get packing fraction = (8 x 3 3 a3 ) / ( 3 x 64 x a3 ) = 0.68

**hence packing
fraction for bcc = 0.68**

An element crystallizes in a body-centered cubic lattice. The
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Calculate the atomic weight of the element.
Express the atomic weight in grams per mole to three significant
digits.

(a) Using the method in Example 8.3, find the distance between
the family of lattice planes with Miller indices [210] for a simple
cubic lattice.
(b) You have a simple cubic crystal with lattice constant of
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(100) planes. Calculate the angle an x-ray beam of wavelength
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Use drawing to show how the iron atoms are packed in the unit
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Use drawings to show how the iron atoms are arranged on the
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planes.
Determine the density of iron (g/cm3) by dividing
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