Lecture 8

Lecture 8

1. doubly degenerate (E) SALCs

   • creating a SALC orthogonal to another
   • for NH3
     • use the projection operator method on r0 which is between r2 and r3 so opposite r1
       • r0=r3-r2

2. orbitals can only interact if they have the same symmetry label

3. orbitals

   • s orbitals relate to the A1 label as this is totally symmetric
   • p orbitals relate to the x, y, z labels
   • reduce a representation of orbitals to find Γ
     • then use projection operators to work out linear combinations of the orbitals in question
       • look at the tables to see which of the neighboring orbitals interact with the labels found

4. once the orbitals that interact have been found you can draw a MO energy level diagram

5. if you need you can generate a 2nd E combination by subtracting one of the bonds representations from the other

6. MO schemes calculated in this way don't take account of hybridisation