Hybridization in coordination compound:
The main application of Valence Bond Theory is to predict hybridization in a coordination compound.
- Hybridization is the concept of mixing of atomic orbital into a new hybrid orbital.
- For example, if one s-orbital combine with one p-orbital it will form a new sp hybrid orbital.
Like that, sp2hybrid orbital = one s-orbital + two p-orbital
sp3 hybrid orbital = one s-orbital + three p-orbital
sp2d hybrid orbital = one s-orbital + two p-orbital + three p-orbital
sp3d2 hybrid orbital = one s-orbital + three p-orbital + two d-orbital
- The coordination number of the metal atom or ion decide the hybridization and geometry of the complex.
For example, if the coordination number is 6, then 6 hybrid orbitals combine among themselves and give sp3d2 hybridization.
- If the coordination number is 6 two possibilities is there i.e.
1. Inner orbital Octahedral complex ( d2sp3hybridization)
2. Outer orbital Octahedral complex ( sp3d2hybridization)
But, both the hybridization leads to Octahedral geometry.
- If the coordination number is 4 there is the possibilities of two types of geometry i.e.
1. Tetrahedral complex ( sp3 hybridization)
2. Square planar complex( dsp2hybridization)
- Outer orbital complex:
Here d-orbital of outermost shell or nth shell participate in bonding. So the hybridization will be sp3d2 (d-orbital present in outer side)
- Inner orbital complex:
Here d-orbital of inner shell or penultimate shell or (n-1)th shell participate in bonding. So the hybridization will be d2sp3 (d-orbital present in inner side)
nice