Question

In calcium fluoride, having the fluorite structure, the coordination numbers for calcium ion (ca2+) and fluoride ion (fтАУ ) are

Answer 1

Simple ionic structures are described by two coordination numbers, one for each type of ion.

Calcium fluoride (CaF2) is an (8, 4) structure,

each cation Ca2+ is surrounded by eight F− anion neighbors,

each anion F− by four Ca2+.

So coordination number of Ca+2=8 and F−=4 ion in CaF2 crystal

Answer 2

Answer:

8 and 4

Explanation:

Calcium fluoride adopts the FCC lattice. The Lattice points for FCC unit cell are at corners and also at the face centers of unit cell.

For face centered cubic (FCC), z=4

The calcium ions in FCC occupy all the corners and the face centers of the cube. Thus, each calcium ion is surrounded by 8 fluorine ions.

The fluorine ions in FCC occupy all the tetrahedral sites. Each fluorine ion is surrounded by 4 calcium ions.