Inversion energy diagram

A potential energy diagram for nng inversion m cyclohexane is shown m Figure 3 18 In the first step the chair conformation is converted to a skew boat which then proceeds to the inverted chair m the second step The skew boat conformation is an inter mediate in the process of ring inversion Unlike a transition state an intermediate is not a potential energy maximum but is a local minimum on the potential energy profile... 

Fig. 3.4. Energy diagram for ring inversion of cyclohexane. [For a rigorous analysis of ring inversion in cyclohexane, see H. M. Pickett and H. L. Strauss, J Am. Chem. Soc. 92 7281 (1979).]...

Fig. 10.1 Zero point energy diagrams, (a) An H or D atom attacking an H2 molecule. The TST isotope effect is negative (inverse, kn > kn) because there is no zero point isotope effect in the ground state, and tunneling is ignored in the TST approximation, (b) An H atom attacking either an H2 or D2 molecule. The isotope effect calculated in the TST approximation is positive (normal, kH > kn) because the zero point isotope effect in the ground state is larger than that in the transition state.

Fig. 1 Energy diagrams illustrating the process of one-photon absorption (IPA) and two-photon absorption (2PA) for (left) a molecule without an inversion center (right) a molecule with an inversion center. The length of each arrow is proportional to the photon energy. The dotted arrows represent possible deexcitation pathways...

Let us consider Fig. 3 in which a double-minimum function represents the Born-Oppenheimer potential for the electronic ground-state of ammonia. This is an energy versus internal inversion coordination diagram. Every value of the inversion coordinate corresponds to a particular nuclear framework for ammonia. The two minima, for example, correspond to pyramidal structures, whereas the maximum corresponds to a planar... 

Energy diagram for ring inversion in cyclohexane. The energy of activation is the difference in energy between the chair and half-chair conformations. The skew boat conformations are intermediates. The boat and half-chair conformations are transition states. 

Figure 17.4 Plausible energy diagram from 30 to [ 1.21- and r2.31-Wittig rearrangement due to different energy harrier for the conformational inversion (see DFT calciilatinns in Ref. 9)...

This inverse kinetic isotope effect on the reductive elimination of alkanes was rationalized by a reversible formation of an alkane complex that would be followed by irreversible dissociation or displacement of the alkane.This pathway is depicted on an energy diagram in Figure 8.2, which also illustrates the origin of the inverse isotope effect. This mechanism would give rise to an apparent kinetic isotope effect that would comprise an... 

Fig. 1 Energy diagram and AG inv of the bowl inversion process of corannulenes [51, 61, 62]...

FIGURE 9.8. A potential energy diagram for pyramidal inversion in an elgiht-electron AHa. 

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