CO2 Revisited with Projection Operators

FIGURE 5.30 Molecular Orbitals of NHj. All are shown with the orientation of the molecule at the bottom. 

In this D2h case, unlike in the C- y point group, each operation is in its own class, and the number of columns above is identical to that in the 2 character table. SALC(Ag) and SALC(5i ) of these oxygen 2s wave functions can be obtained by multiplication of each outcome by the characters associated with each operation of these irreducible representations, followed by addition of the results  

Normalization results in the expected group orbitals. In all molecules with two identical 

The 2p group orbitals also possess Ag and 5i symmetry. The basis for the projection operator method is again the Ag group orbital, with the same signs of the orbital lobes pointing toward the center. 

Extension to the SALCs affords the anticipated wave function equations and group orbitals the signs are defined on the basis of the orientation of the orbitals relative to the central atom. 

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