The concept of hybridization was introduced by Pauling and Slater. HybridizationIt is defined as the intermixing of dissimilar orbitals of the same atom but having slightly different energies to form same number of new orbitals of equal energies and identical shapes. The new orbitals so formed are known as hybrid orbitals.
How to determine type of hybridization: The structure of any molecule can be predicted on the basis of hybridization which in turn can be known by the following general formulation,
H = (1/2) (V+M+A)
Where; H = Number of orbitals involved in hybridization viz. 2, 3, 4, 5, 6 and 7, hence nature of hybridization will be sp, sp2, sp3, sp3d, sp3d2, sp3d3 respectively.
V = Number electrons in valence shell of the central atom,
M = Number of monovalent atom
C = Charge on cation,
A = Charge on anion
Characteristics of hybridization
(1) Only orbitals of almost similar energies and belonging to the same atom or ion undergoes hybridization.
(2) Hybridization takes place only in orbitals, electrons are not involved in it.
(3) The number of hybrid orbitals produced is equal to the number of pure orbitals, mixed during hybridization.
(4) In the excited state, the number of unpaired electrons must correspond to the oxidation state of the central atom in the molecule.
(5) Both half filled orbitals or fully filled orbitals of equivalent energy can involve in hybridization.
(6) Hybrid orbitals form only sigma bonds.
(7) Orbitals involved in p bond formation do not participate in hybridization.
(8) Hybridization never takes place in an isolated atom but it occurs only at the time of bond formation.