Configurational curves

If the energy gap between the configuration curves R- X and R -X is large (bold lines, Fig. 6a) then both the ground and excited state curves (dotted lines, Fig. 6a) are repulsive at all R--X distances. This is because mixing... 

The energy diagram describing NaCl dissociation is quite different to that observed for R—X and [R—X] dissociation. This is because for NaCl the two relevant configuration curves cross (Herzberg, 1950 Levine and Bernstein, 1974), in contrast to the situation for R—X and (R—X) where the two curves are separated. The well-known NaCl curve crossing is illustrated in Fig. 7. At infinite separation Na Cl is more stable than... 

Fig. 7 Energy diagram showing the avoided crossing of Na" -Cl and Na+Cl configuration curves. State curves resulting from configuration mixing are indicated by dotted lines...

Two-configuration reactions. Since for most organic reactions one or more covalent bonds are broken while one or more new bonds are formed a reaction profile may be schematically generated as indicated in Fig. 8. For the case in which at least one reactant is a closed shell species, two configuration curves, reaction barrier. The reactant configuration, [Pg.117]

A question of particular importance is whether the intersection of two configuration curves will result in a real crossing, as indicated in [6a], or an avoided crossing as indicated in [6b]. The general rule which governs the... 

Fig. 22 Energy diagram for ground [17], , excited [18], and product [19] configurations for the photochemical hydrogen abstraction reaction of ketones. Reaction proceeds from reactants up to point A (by photochemical excitation), along the , excited configuration curve, [18], undergoes an avoided crossing with [19] (point B) and down to product...

Fig. 28 Energy diagram illustrating the configuration curves that contribute to the deprotonation reaction of a nitroalkane. The major configurations are the reactant configuration [44], the oxyanion configuration [45], and the carbanion configuration [46]...

A 6-configuration curve is also shown which excludes intra-atomic correlation terms. 

The CD spectra for the less soluble forms of the complexes are shewn in Figure 12, in which the calculated configurational curve of an active form of [Go(Nb,0.g)(L-val)(NH,)]6 is included. In contrast to the CD spectrum of theJtame complexes, the CD spectra of the hexaniobato complexes deviate considerably from the additivity rule, the reason for such difference between the [CoCty and the [GoO N-] types being unknown. 

The CD spectral data of the (—)j89-glycinato complex is cited in Table 5.6. The so-called additivity rule of the configurational and vidnal contributions permitted to find that the configurational curves for the diastereomeric complexes are similar to the CD curve for the enantiomeric glycinato complex. 

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