Mulliken charge transfer picture

The wavefunction description Eq. (10.3) corresponds closely to the Mulliken charge transfer picture of PT [33] shown in Fig. 10.2, in which a non-bonding (ng) electron of the base is transferred into an antibonding orbital of the acid. A... 

Figure 10.2 Qualitative orbital energy diagram of the Mulliken charge transfer picture for the two VB states of the H-bond PT complex AH—B.

The net charges and net spin densities obtained from Mulliken population analysis are listed in Table 3. The net charges of An are all ca. +2.9 except for Pa, for which the charge is +3.5. For all of the complexes, the charges on the C atoms are all about -0.2, and the H atoms are essentially neutral, consistent with the picture that the charge transfer occurs primarily between the Cpn orbitals to the An orbitals, as expected. The net spin density increases from Th to Am, consistent with the increase in the number of metal-localized electrons in the series of actinocenes. 

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