Wilkinson's Catalyst: Hybridization and Shape of Central Metal Ion

Wilkinson's catalyst is a homogeneous catalyst used in organic reactions such as hydrogenation of alkenes and isomerization of alkanes. The catalyst is named after its discoverer, Geoffrey Wilkinson, who was awarded the Nobel Prize in Chemistry in 1973 for his work on organometallic chemistry.

Hybridization of Central Metal Ion
The central metal ion in Wilkinson's catalyst is a rhodium (Rh) atom. The hybridization of rhodium in Wilkinson's catalyst is sp3d2. This is because the rhodium atom has five d-electrons, which can hybridize with one s-orbital and three p-orbitals to form five hybrid orbitals. These hybrid orbitals are then used to form five sigma bonds with the surrounding ligands.

Shape of Central Metal Ion
The rhodium atom in Wilkinson's catalyst has a square planar geometry. This means that the rhodium atom is surrounded by four ligands, which are arranged in a square plane around the central metal ion. The four ligands are triphenylphosphine (PPh3) molecules, which are coordinated to the rhodium atom through their phosphorus atoms.

The square planar geometry of Wilkinson's catalyst is due to the sp3d2 hybridization of the rhodium atom. The five hybrid orbitals of the rhodium atom are arranged in a trigonal bipyramidal geometry, with three hybrid orbitals pointing towards the corners of a triangle and two hybrid orbitals pointing towards the top and bottom of the trigonal bipyramid. The four ligands then occupy the equatorial positions of the trigonal bipyramid, resulting in a square planar geometry around the central metal ion.

In conclusion, the hybridization of the central metal ion in Wilkinson's catalyst is sp3d2, and the shape of the central metal ion is square planar. These properties of Wilkinson's catalyst are important for understanding its reactivity and its ability to catalyze organic reactions.

Answe: Wilkinson's catalyst is an important organic reagent. The formula of Wilkinson’s catalyst is RhCl(PPh3)3
where Rh is rhodium and Ph is the phenyl group.
Rhodium is a d block element having an electronic configuration of 5s2,4d7