hybridisation - babasaheb bhimrao ambedkar university
TRANSCRIPT
HYBRIDISATION
Rules for hybridisation
• Only orbitals of smaller energies belonging to the same atom or ion can hybridize together
• Number orbitals are similar umber of hybrid orbitals produced is equal to the number of orbitals undergoing hybridization. Hybrid bonds are stronger than the single non hybridized bonds of comparable energy
• Most of the hybrid orbitals are similar but they are not necessarily identical in shape. They differ from one another in their orientation in space.
• For equivalent hybrid the orientation in space is determined by number of orbitals mixed and which of x, y and z axis is preferred
• From the type of hybridization one can predict the geometry and bond angle of a molecule
• An orbital which has been used to build up a hybrid orbital is no longer available to hold electron in its pure form
Types of hybridisation
• sp – hybridisation (mixing of s and pz orbitals)
• Linear (or diagonal hybrid orbitals
Example: BeCl2
sp2 hybridisation• sp2 – hybridisation (mixing of s px and pz orbitals)
• Trigonal planar (or triangular) hybrid orbitals
Example: BeCl3Trigonal planar shape
SnCl2 (Angular or bent (V-shape)
NO3Planar triangular shape
sp3 hybridisation
• sp3 – hybridisation (mixing of s + px + pz + pz orbitals)
• Tetrahedral hybrid orbitals
pz
Example: CH4
• Tetrahedral
Trigonal pyramidal V-shaped Linear
:NH3 H2O HF
sp3d hybridisation
• sp3d – hybridization
• (mixing of s + px + pz + pz + dz2orbitals)
• Trigonal bipymramidal
• Five hybrid orbitals are non equivalent
• three equatorial hybrids (or basal or planar hybrids)
• Two axial or polar hybrids
Example
PF5, :SF4, ClF3
Trigonal bipyramidal Distorted bipyramidal T-shaped
sp3d2 hybridisation
• sp3d2 – hybridisation (mixing of s + px + pz + pz + dz2 + dx2-y2 orbitals)
• octahedral
Example:
SF6, :IF5 XeF4
Octahedral Square pyramidal Square planar
sp3d3 hybridisation
• sp3d3 – hybridisation (mixing of s + px + pz + pz + dxy + dyz + dyz orbitals)
• Pentagonal bipyramidal
• Example: IF7, XeF6
dsp2 hybridisation
• dsp2 – hybridisation (mixing of s + px + py + dx2-y2orbitals)
• Square planar hybrid orbitals
dsp3 hybridisation
• dsp3 – hybridisation (mixing of s + px + py + pz + dx2-y2orbitals)
• Square pyramidal hybrid orbitals