MOLECULAR SIZE SHAPE EFFECTS IN THE SEPARATION OF THE MONOSUBSTITUTEDALKYL PYRIDINES USING CAPILLARY ELECTROPHORESIS/

A series of monosubstituted alkyl pyridines have been used to investig ate the presence of molecular size/shape effects in capillary electrop horesis and the applicability of various descriptors in discriminating not only between derivatives of differing chain length but also betwe en positional isomers. Although van de Waals' radii and Offord's param eters are extremely good descriptors in predicting the relative mobili ties of the derivatives, a further descriptor involving length and/or diameter of the molecule is necessary for discrimination between the p ositional isomers.