Orbital language

In molecular orbital language, back donation (or back bonding) means considerable participation of empty ligand orbitals (usually r ) in the occupied T-molecular orbitals mostly localised on the metal. We are fortunate to have the simple words "back donation" to describe such a state ot affairs. 

Acknowledging the importance of the pioneering idea of Bersuker s orbital vibronic constants [8] we will follow here also an orbital perspective. The orbital language, namely, the effective one-electron picture, relates with the vibronic problems by the fact that the involved electron-nuclear interactions is truly monoelectronic in nature. The Bersuker s traditional formula is... 

We still have the problem of how to talk about all these highly delocalized orbitals, and how to retrieve a local, chemical, or frontier orbital language in the solid state. There is a way. 

There is, however, a way to retrieve a frontier orbital language in the solid state. We cannot think about a single level, but perhaps we can talk about bunches of levels. There are many ways to group levels, but one pretty obvious way is to look at all the levels in a given energy interval. The density... 

In molecular orbital language the electronic configuration of the first excited states of N3 is. .. (7rg) 7r,. (To simplify the discussion the orbitals below were omitted see Figure 5.) As in the case of GO2,... 

Glossoa and Gray ° related the 285 and 215 nm bands of alkyl azides (bands I and II) to the single transition of at 230 nm. If the latter is a <- 2/ transition (see foregoing discussion) then under an off-axis perturbation (section I.G) these bands should split into two components. In molecular orbital language, I and II are assigned to 7rv(a") (a ) and jSp(a )-> 7r (a") transitions (see... 

While the interaction between a and tt electrons may be ignored, that between n and tt or tt and tt electrons is considerable. Having discussed the different types of valence electrons, we shall now mention the various transitions responsible for electronic spectra. Here again, we shall use the molecular orbital language without going into its details. The transitions have been discussed in detail by Duncan and Matsen2. 

Definition and representation of the model space. To characterize (the basis functions of) the model space, we make use of fhe number of occupied valence orbifals and the number of unoccupied core-valence orbitals. Within the orbital language of... 

Up to now, the spin-orbital notion was used. However, let us switch to the orbital language that is frequently used for MC-SCF considerations. 

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