Molecular orbital diagrams, calculated

Density Functional Theory, DFT (B3LYP), CASSCF (Complete Active-State Self-Consistent Field) and MRSD-CI (Multi-Reference Single-Double Correlation Interaction) calculations on the diatomic units AuO, AuO", AuO " and AuO " clearly show that stability of Au-0 bond reduces in this order. This trend is consistent with the molecular orbital diagram of AuO molecule presented in Fig. 10. 

Various theoretical methods and approaches have been used to model properties and reactivities of metalloporphyrins. They range from the early use of qualitative molecular orbital diagrams (24,25), linear combination of atomic orbitals to yield molecular orbitals (LCAO-MO) calculations (26-30), molecular mechanics (31,32) and semi-empirical methods (33-35), and self-consistent field method (SCF) calculations (36-43) to the methods commonly used nowadays (molecular dynamic simulations (31,44,45), density functional theory (DFT) (35,46-49), Moller-Plesset perturbation theory ( ) (50-53), configuration interaction (Cl) (35,42,54-56), coupled cluster (CC) (57,58), and CASSCF/CASPT2 (59-63)). 

Steiger et al. (205) suggested the Coni-02- structure based on femtosecond dynamics. Molecular orbital diagrams (24,25) and earlier LCAO-MO-SCF calculations (29) support this assignment. No ab initio or DFT results on the electronic structure of CoP-02 have been reported so far. 

Fig. 11. Molecular orbital diagram for the MojClJ" ion based on SCF-Xa-SW calculations the highest tilled level is 22>2g(fi) (199).

Figure 12. Molecular orbital diagram for an FegOjg cluster used to understand the orbitals involved in Fe Fe3 charge transfer. The absorption band observed near 13,000 cm 1 in the spectra of mixed-valence silicates is due to the transition from the Fe2 (t2g)- Fe3+(t2g) orbitals. A transition state calculation for that energy in the cluster presented here gives 10,570 cm"1 in fair agreement with experiment.

The stability of the trihalogen intermediate is greatest when the least electronegative atom is in the central position. This complex is expected to be bent by examination of the appropriate Walsh molecular orbital diagrams and it is possible that the reaction is constrained to take place only for certain preferred interaction geometries. Trajectory calculations [561] for Cl + Br2, I2 and Br + I2 could not reproduce the experimental results with any surface having a potential well that preferred collinear approach of the reagents. 

Fig. 6. Qualitative molecular orbital diagram for the Cp2M2(/r-CO)3 molecules 8-13 based on calculations for Cp2Fe2(M-CO)3 (8) (79). The S level is the HOMO for the Group 7 molecules whereas there are two unpaired electrons in the ir level for the Group 8 species.

FIGURE 1. Molecular orbital diagram for (CO)3Co( -C3H3) based on Fenske-Hall calculations ... 

Fig. 2.23. Molecular-orbital diagram for the FeO " cluster (at Fe-O distance of 2.17 A) calculated using the MS-SCF-2fa method (see Section 3.10). The highest occupied orbital is the 2/2gj, containing one electron (after Loeffler et al., 1974 reproduced with the publisher s permission).

Fig. 4.10. Molecular-orbital diagram for the SiO/ cluster from MS-SCF-Aql calculation (after Tossell et al., 1973b reproduced with the publisher s permission).

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