Which of the following is not true about the voids formed in 3 dimensional hexagonal close packed structure?

Options

A. A tetrahedral void is formed when a sphere of the second layer is present above triangular void in the first layer
B. all the triangular voids in the first layer
C. tetrahedral voids are formed when the triangular voids in the second layer lie above the first layer and the triangular shpes of these voids do not overlap
D. Octahedral voids are formed when the triangular voids in the second layer exctly overlap with similar voids in the first layer

Answer

C,D

Explanation

tetrahedral voids are formed when the triangular void in the second layer lie excatly above the triangular voids in the first layer and the triangular shape of these voids oppositely overlap .

Octachral voids are formed when trigular void of second layer is not exactly overlap with similar void in first first layer.