Antifluorite structure is for `:`

Options

A. Oxide ions have a cubic close packed arrangement and `Na^(+)` occupy all the eight tetrahedral voids
B. Oxide ions have a cubic close packed arrangement and `Na^(+)` occupy all the octahedral voids
C. `Na^(+)` ions have a cubic close packed arrangement and `O^(2-)` occupy all the octahedral voids
D. `Na^(+)` ions have a cubic close arrangement and `O^(2-)` occupy all the tetrahedral voids.

Answer

A

Explanation

In antifluorite structure like `Na_(2)O,O^(2-)` ions occupy half of the cubic holes and `Na^(+)` ions occupy all the tetrahedral voids. Each, `O^(2-)` ion is surrounded by `4O^(2-)` ions. It has 4:8 coordination.