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100   •  Chapter 3    /    The Structure of Crystalline Solids


            3.36  Determine the indices for the directions shown          z                   z
                in the following cubic unit cell:





                                                                            a                    a
                                                                             2                   2
                                                                a                   a
                                                                 3                   3
                                                                                  a 1                 a 1
                                                                        (c)                  (d)




                                                           3.42  Sketch the [0110] and [2 2 4 3] directions in a hex-
                                                               agonal unit cell.
                                                           3.43  Using Equations 3.11a–3.11d, derive expressions
                                                               for each of the three U, V, and W indices in terms
            3.37  (a)  What are the direction indices for a vector  of the four u, y, t, and w indices.
                                     1
                                   1
                that passes from point   0   to point       in a cubic
                                             3 1 1
                                   4
                                     2
                                             4 2 2
                unit cell?                                 Crystallographic Planes
                (b)  Repeat part (a) for a monoclinic unit cell.  3.44  (a)  Draw an orthorhombic unit cell, and within
                                                               that cell, a (021) plane.
            3.38  (a)  What are the direction indices for a vec-
                                                  2 3 1
                                      1 1
                tor that passes from point    0  to point      in a  (b) Draw a monoclinic unit cell, and within that
                                      3 2
                                                  3 4 2
                tetragonal unit cell?                          cell, a (200) plane.
                (b)  Repeat part (a) for a rhombohedral unit cell.  3.45  What are the indices for the two planes drawn in
                                                               the following sketch?
            3.39  For tetragonal crystals, cite the indices of direc-
                tions that are equivalent to each of the following
                directions:
                (a) [011]
                (b) [100]
            3.40  Convert the [110] and [001]  directions into the
                four-index Miller–Bravais scheme for hexagonal
                unit cells.
            3.41  Determine the indices for the directions shown
                in the following hexagonal unit cells:

                          z                    z




                                                           3.46  Sketch within a cubic unit cell the following
                            a                     a            planes:
                             2                     2
                                                               (a)  (101)   (e)  (111)
                                                               (b)  (211)
                a                    a                                    (f)  (212)
                 3                    3
                                                               (c)  (012)  (g)  (312)
                                  a 1                  a 1
                        (a)                   (b)              (d)  (313)   (h)  (301)
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