HYBRIDISATION

DEFINITION

HYBRIDISATION IS THE CONCEPT OF MIXING OR MERGER OF ORBITALS OF AN ATOM HAVING NEARLY EQUAL ENERVIES, TO PRODUCE ENTIRELY NEW ORBITALS WHICH ARE EQUAL IN NUMBER TO THE MIXING ORBITALS, THE HYBRIDISED NEW ORBITALS WIL HAVE EQUAL ENERGIES: IDENTICAL SHAPES AND ARE SMMETRICALLY PLACED IN SPACE.

CINDITIONS FOR HYBRIDISATION OF ATOMIC ORBITALS

1. THE ORBITALS OF AN ISOLATED, SINGLE ATOM ONLY COULD UNDERGO HYBRIDISATION.
2. THE HYBRIDISING ORBITALS MUST DIFFER ONLY SLIGHTLY IN THEIR ENERGY CONTENT.

CHARACTERISTICS OF HYBRID ORBITALS

CHARACTERISTICS OF HYBRID ORBITALS

1. THE NUMBER OF HYBRIDISED ORBITALS IS EQUAL TO THE NUMBER OF PURE ATOMIC ORBITALS WHICH MIX UP.
2. A HYBRID ORBITAL CAN HAVE ONLY TWO ELECTRONS AS THE PURE ATOMIC ORBITALS. THE TWO WLWCTRONS MUST HAVE OPPOSITE SPINS .
3. THE ELECTRON WAVES IN HYBRID ORBITALS REPEL EACH OTHER. SO THEY TEND TO BE AS FAR AWAY AS POSSIBLE.
4. THE HYBRID ORBITALS DISTRIBUTE THEMSELVES IN SUCH A WAY THAT THEY ASSUME THE DIRECTION O THE DOMINATING ORBITALS.

SP HYBRIDISATION

SP HYBRIDISATION

ONE S AND ONE P ORBITALS MIX AND GIVE TWO IDENTICAL HYBRID OR BITALS. THIS ISKNOWN AS SP HYBRIDISATION. THESE HYBRID ORBITALS ARE CO-LINEAR. THIS BOND ANGLE IS 180 DEGREE.

EXAMPLE: BeCl2

SP2 HYBRIDISATION

STRUCTURE OF SP2 HYBRIDISATION

SP2 HYBRIDISATION:

ONE S ORBITAL AND P ORBITALS MIX AND GIVE THREE IDENTICL HYBRID ORBITALS. THIS IS KNOWN AS SP2 HYBRIDISATION. THESE HYBRID ORBITALS LIE IN THE SAME PLANE. THE SHAPE IS PLANE TRI ANGULAR. THE BOND ANGLE IS 120 DEGREE.

EXAMPLE: ETHYLENE

SP3 HYBRIDISATION

STRUCTURES OF SP3 HYBRIDISATION

SP3 HYBRIDISATION

ONE S ORBITAL AND THREE P ORBITALS MIX AND GIVE FOUR INDENTICAL ORBITALS. THIS IS KNOWN AS SP3 HYBRIDISATION. THE FOUR HYBRID ORBITALS ARE ORIENTED TOWARDS THE FOUR CORNERS OF A REGULAR TETRAUEDRON. THE BOND ANGLE IS 109 DEGREE 28'.

EXAMPLE: METHANE