Theoretical Status

It has been suggested that, regardless of the transition state structure during solvolysis, the norbomyl ion might have yet another structure under the stabilizing influence of strong acid media. Before considering those systems it is appropriate to discuss the current theoretical status as provided by molecular orbital calculations. 

A rigorous all-electron, non-empirical ab initio calculation ought to be able to define the bond lengths, angles and charge distribution and hence the structure of an unsolvated norbomyl cation. The most 

Goetz and Allen used Pople s STO-3G and 4-3IG basis sets which are representative of small and medium sets to obtain points on the potential energy surface of the ion (Hehre et al., 1969 Ditchfield et al., 1969). These sets had proved useful in computing the potential surface for the CsHt ion (Radom et al., 1971) and it was assumed they would be valuable in describing the C-1 C-2 C-6 portion of the norbomyl ion. 

For the non-classical ion an energy minimum was deduced with a bond length of 1-40 A between C-1 and C-2 and 1-837 A between C-1 and C-6. The energy was —268-04377 Hartrees or about 4-3 kcal mole higher than the classical structure. 

The energy difference is expected to be reduced and perhaps eliminated when the calculations are repeated utilizing the 4-3IG basis set because of Pople s experience with the C3H7 ion. The non-classical form should be preferentially stabilized by the improved representation of the atomic orbitals, which should enable calculations to give a better account of the long bonds and three-centre ring. 

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The functional group in ligand field studies the empirical and theoretical status of the angular overlap model. M. Gerloch and R. G. Woolley, Prog. Inorg. Chem., 1984, 31, 371-446 (87). 

M. Gerloch, R.G. Woolley, The Functional Group in Ligand-Field Studies The Empirical and Theoretical Status of the Angular Overlap Model , in Prog. 

Studies The Empirical and Theoretical Status of the Angular Overlap Model 31 371... 

This short treatise is intended to provide the reader with a concise summary of the current theoretical status of the molecular structure and geometry concepts. A fully quantum-mechanical treatment of molecules is employed where necessary. The relevance of stationary states of isolated molecules is discussed and the notion of molecular geometry is contrasted with that of molecular structure. 

The Kramers theory and its extensions have found many applications since the original work by Kramers. Recent application of the non-Markovian theory in the low-friction limit to thermal desorption was described by Nitzan and Carmeli. Another novel application of the Markovian theory is to transition from a nonequilibrium state of a Josephson junction. In what follows we shall briefly review the recent application of the generalized Kramers theory to chemical rate processes. More detailed reviews of the exjjerimental and theoretical status of this field may be found in Hynes. ... 

It could clarify the theoretical status of the absorbing potentials used in actual calculations to avoid spurious recurrences caused by the basis set incompleteness [11,12,31]. 

Borsboom, D., MeUenbergh, G., and Van Heerden, J. The theoretical status of latent variables. Psychological Review, 110(2) 203, 2003. 

Uzan, J.-P., The fundamental constants and their variation observational and theoretical status. Rev. Mod. Phys., 75,403, 2003. 

Despite the nonrigorous theoretical status of counterion condensation, many of its predictions find direct support in experiment. As will be seen, properties such as osmotic pressure, ion activity coefficients, and coimterion diffusion coefficient... 

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