Unit cell nickel arsenide

Structure of nickel arsenide showing (a) 3 unit cells, (b) a single unit cell NiaAsa and its relation to (c) the unit cell of the layer lattice compound Cdia (see text). 

FIGURE 1.36 (a) The unit cell of nickel arsenide, NiAs. (For undistorted hep c/a=1.633, but this ratio is found to vary considerably.) Ni, blue spheres As, grey spheres, (b) The trigonal prismatic coordination of arsenic in NiAs. 

Fig. 91. Unit cell of nickel arsenide (hexagonal system).

Fig. 8.02. (a) Plan of the unit cell of the hexagonal structure of nickel arsenide, NiAs, projected on a plane perpendicular to the z axis, (b) Clinographic projection of the same structure. The two As atoms represented by heavy circles are those within the unit cell the others lie outside the cell but have been added to show the co-ordination about the Ni atom at o, o,... 

Fig. 14.10 Two views of the unit cell (defined by the yellow lines) of the nickel arsenide (NiAs) lattice colour code Ni, green As, yellow. View (a) emphasizes the trigonal prismatic coordination environment of the As centres, while (b) (which views (a) from above) illustrates more clearly that the unit cell is not a cuboid.

The unit cell for nickel arsenide is shown below. What is the formula of this compound ... 

The unit cell of nickel arsenide is shown here, (a) What type of lattice does this crystal possess (b) What is the empirical formula ... 

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