Table 5.6 gives the results of a self-consistent field (SCF) quantum chemical calculation for H₂O using an orbital basis set of the atomic orbitals of O and the LGOs of an H---H fragment. The axis set is as defined in Fig. 5.15. 

(a) Use the data to construct pictorial representations of the MOs of H₂O and confirm that Fig. 5.15 is consistent with the results of the calculation. 

(b) How does MO theory account for the presence of lone pairs in H₂O?

Table 5.6

Figure 5.15

Transcribed Image Text:

Atomic orbital or ligand group orbital 0 2s 0 2px O 2py O 2p: H---H LGO(1) H---H LGO(2) Percentage character of MOs with the sign of the eigenvector given in parentheses 24 71 (+) 0 0 0 29 (+) 0 0 0 59 (+) 0 0 41 (-) 7(-) 0 0 85 (-) 8 (+) 0 0 100 (+) 0 0 0 0 0 41 (-) 0 0 59 (-) 2/6 22 (-) 0 0 15 (+) 63 (+)