On the basis of VBT explain the hybridization, geometrical shape and magnetic property of `[CoF_(6)]^(3-)`, hexafluorido cobaltate (III) ion.

Explanation

In `[CoF_(6)]^(3-)`, the oxidation state of `Co` is `+3`. The electronic configuration `Co` in `+3` oxidation state is
`C_(o)^(3+)-[Ar]3d^(6)4S^(@)`

Since `F^(-)` ion provides a weak field ligand, there fore pairing doesnot takes place.
One 4s, three 4p and two 4d - orbitals hydridised to yield six `sp^(3)d^(2)` hybrid orbitals pointing toward the six corer of an octahedron. These six hybrid orbitals overlaps with orbitals of six `F^(-)` ligands.

Geometry - Octahedran
Hybridisation - `Sp^(3)d^(2)`
Magnetic property - paramagnetic