Cluster and principal component analysis of the solvent effects on the C=Ostretching frequency of acetophenone

The solvatochromic shift of the C=O stretching frequency of acetophenone is studied by cluster (CA) and principal component analysis (PCA) confirming our previous results about the determining contributions to the polarity, p olarizability, and electrophilicity of the medium on this effect. It is sho wn that the used combination of Varimax mode of PCA and multiple regression (apportioning modeling) makes it possible to obtain absolute principal com ponent scores (APCS), which include the solvent parameters describing defin ite solute-solvent interactions. The adequateness of the suggested chemomet ric model is checked by "reverse" CA of 25 solvents as objects with respect to the APCS calculated.