Solute distortion energy

The treatment of loss of R from sterns is trivial dissociation occurs along some kind of bond dissociation curve to give, in the imagined limit, metal and a car-banion. In solution at least, both fragments will interact with the environment at bond distortion energies wefl below the dissociative limit. 

Here, q refers to the permanent charges of solvent molecules, p to the solvent induced dipoles, and p is the solute charge density. The last term in Equation (4.152) is the distortion energy of the solute, i.e., the energy spent in polarizing it. 

In order to clarify the role played by the solvent in the stabilization of the different structures it is useful to split the AGint term into two terms A int and AGsoiv. The last term, AGsoiv, provides the solvent distortion energy, i.e., the energy spent in changing the solvent structure from the initial to the final state. The term A nt accounts for the difference in the solute-solvent interaction energy between the final and initial states. For a non-polarizable solvent this term reads... 

The lattice distortion energy, W E ), generated by a solute atom in the bulk can be calculated by using elastic continuum theory as " ... 

All in aqueous solution at 25° C rate constants are in s Calculated rates are based on distortion energies calculated at the 3-2IG level some compounds were treated at... 

The formation of banded textures in thin-film samples of solutions of hquid crystalline polymers (LCPs), subjected to shear, has been reported in the literature since 1979 [15]. Because of the symmetrical properties of the liquid crystal solutions, large domains of weU-oriented polymer chains are formed during shear flow, while defects are squeezed into small regions. The shear accounts for an additional energy stored in the solution. When the shear is stopped, the system will first relax with a characteristic time fb to a transient state. In this state the distortion energy is minimized, and the orientational order is kept, resulting in a banded stmcture. This behavior is observed only if two conditions are fulfilled [16] ... 

The two static solutions are approached at z oo. The interfacial energy is computed most easily by using p as an independent, and the distortion energy density W — Kp as a dependent variable. Then Eq. (17) is rewritten as... 

Here, we introduce the distortion energy of the QM solute in solution,... 

The last statement is proven (using the same theoretical concepts) when the Raman spectra of PHTh (or POTh) in the solid and solution phases are compared (fig.17). In agreement with the electronic spectra of the same samples, in solution the energy gap is larger because the molecule is distorted in a structure which we label as 20 (with the torsional angle 0 yet unknown) while in the solid the HOMO-LUMO transition is red shifted since the systems approaches coplanarity in a 2 structure with smaller. The observed Raman frequency and intensity dispersion is the following for the solid 1515, 1448 and 1380 cm , for the solution 1517, 1475 cm" and (too weak ), in agreement with the predictions by ECC theory. 

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