The validity of some of the assumptions made in the interpretation of transport data for poly-ionic solutions has been questioned [1, 2]. However, no real quantitative estimate of the errors has as yet been established and the question of which molecular parameters are actually attainable by transport measurements remains to be answered. [Pg.261]

In conclusion, the solvation equation could be applied to describe several liquid chromatographic partition systems in terms of their sensitivity towards molecular properties. The standard error for estimating the retention data was low and the multiple correlation coefficients of the solvation equations were high. The parameters of the solvation equations help us to understand and describe the different selectivity of the stationary phases, and also to understand the retention of the compounds in a given system based on its molecular properties. [Pg.577]

The authors of this work proposed a semi-empirical scheme for the calculation of 13C chemical shift tensors based on the bond polarization theory (5). This method can reproduce 13C chemical shift tensors with deviations from experiment comparable to the errors of the ab initio methods. One major advantage is that the calculations can be performed for large molecular systems with hundreds of atoms even on a PC computer. In contrast to the ab initio method a set of empirical parameters is needed for the calculations. In the case of the bond polarization theory these parameters can be estimated directly from experimental chemical shifts solving a set of linear equations. [Pg.93]

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