Which of the following statement is correct in the zinc blende type structure of an ionic comound?

Options

A. Coordination number of each cation and anion is `2`.
B. Coordination number of each cation and union is `4`.
C. Coordination number of each cation and union is `6`.
D. Coordination number of each cation and union is `8`.

Answer

B

Explanation

`ZnS` has diamond cubic structure in which `S^(2-)` ions from `bcc` lattice and `Zn^(2+)` ions are present in alternalte `TV_(s)`.
`Z_(eff)` of `S^(2-) = 4` (corner `+` face centre `= 3 + 4`).
`Z_(eff)` of `Zn^(2+) = 4`
(Total `TV_(s) = 8`, alternate `TV_(s) = 4`).
So `Z_(eff)` of `ZnS = 4`
Hence, the formula is `Zn_(4)S_(4)`.
So coordination number of `Zn^(2+)` and `S^(2-)` is `4` each.