Molecular Property Correlation in Haloethanes with Geometric Volume

A large number of molecular and thermodynamic properties of the alkane molecules containing up to eight carbon atoms have been correlated with a newly developed theoretical index, geometric volume. The geometric volume gives an estimate of the molecular size and is characteristic of each alkane molecule. The n-alkanes generally show a smooth positive variation in their molecular properties with the geometric volume while the isomers correlate differently in many cases. In such cases, however, a single bilinear correlation equation may be derived for the entire set of alkane molecules. It is possible to obtain more realistic and meaningful correlation equations, if the regularities in the molecular properties of the alkane molecules are properly identified by graph theoretical ordering of the structure.