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** Effect of Particle Geometric Changes **

** Geometrical Changes in Excited States **

Figure 9.4. The interplay between electronic structure (VB bonding pattern) and geometrical change on the potential energy surface. |

The molecular models of rubber elasticity relate chain statistics and chain deformation to the deformation of the macroscopic material. The thermodynamic changes, including stress are derived from chain deformation. In this sense, the measurement of geometric changes is fundamental to the theory, constitutes a direct check of the model, and is an unambiguous measure of the mutual consistency of theory and experiment. [Pg.258]

The question we ask here is whether the surface heterogeneity, either energetical or geometrical, changes the properties of the critical region and whether the transition retains its second-order character. [Pg.267]

It is thus evident that the experimental results considered in sect. 4 above are fully consistent with the interpretation based on absolute reaction rate theory. Alternatively, consistency is equally well established with the quantum mechanical treatment of Buhks et al. [117] which will be considered in Sect. 6. This treatment considers the spin-state conversion in terms of a radiationless non-adiabatic multiphonon process. Both approaches imply that the predominant geometric changes associated with the spin-state conversion involve a radial compression of the metal-ligand bonds (for the HS -> LS transformation). [Pg.92]

For each molecule, calculate the overall energy barrier for ring inversion in each direction. Use this barrier to calculate the half-life (t./,) of an individual molecule at 298 K (use equation 2). Which molecule inverts most rapidly Most slowly Why (Hint What geometrical changes are required for inversion ) [Pg.81]

** Effect of Particle Geometric Changes **

** Geometrical Changes in Excited States **

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