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

Options

A. A tetrahdral void is formed when a sphere of the second layer is present above trinaglar void in the first layer.
B. All the triangular voids arenot covered by the spheres of the second layer.
C. Tetrahedral voids are formed when the traingular voids in the seconds layer lie above the triangular shapes of these boids do not overlap.
D. Octadrdral obids are fomed when the traingular voids in the second later exactly overlap with similar voids in the first layer.

Answer

C, D

Explanation

is not ture because octahedral voids are formed when triangular voids in the second layer lie the triangular voids of the first layer.
(d) is not true because octadedral void is combination of two trianglar voids one with vertex upward and the other with vertex downward and not their overlap.