# Figure 16.9: Three cubic unit cells and the corresponding lattices.

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Figure 16.9: Three cubic unit cells and the corresponding lattices.

The closet packing arrangement of uniform spheres.

When spheres are closest packed so that the spheres in the third layer are directlly over those in the first layer (aba) the unit cell is hexagonal prism illustrated here in red

A toy slide puzzle

A section of a surface containing copper atoms (red) and an indium atom (yellow).

When spheres are packed in the abc arrangement, the unit cell is face-center cubic.

Figure 16.16: The indicated sphere has 12 equivalent nearest neighbors.

The net number of spheres in a face-centered cubic unit cell.

Volume of a unit cell (2r, 4r, r)

In the body-centered cubic unit cell the spheres touch along the body diagonal.

Simple Cubic Cell

On the face of the body-centered cubic unit cell.

The relationship of the body diagonal (b) to the face diagonal (f) and the edge (e) for the body-centered cubic unit cell.

Sodium chloride crystals are brittle Structure of NaCl: an ionic crystal Why 6-coordinated ?

The locations (gray x) of the octahedral holes in the face-centered cubic unit cell.

The octahedral hole (shown in yellow) lies at the center of six spheres that touch along the edge of the square

(a) A simple cubic array with X - ions, with an M + ion in the center (in the cubic hole) (b) The body diagonal b equals

Figure 16.36: The holes that exist among closest packed uniform spheres

Figure 16.38: (a) The tetrahedral hole (b) The center of the tetrahedral hole

One packed sphere and its relationship to the tetrahedral hole

(a) The location (x) of a tetrahedral hole in the face-centered cubic unit cell.(b) one of the tetrahedral (c) the unit cell (d) The alternate tetrahedral

Figure 16.43: Defects in crystalline ionic solids

Figure 16.22: The electron sea model for metals postulates a regular array of cations in a "sea" of valence electrons.

Grains of nanophase palladium magnified 200,000 times by an electron microscope. Source: Nanophase Technologies Corporation

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