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Title: Graph-theoretical analysis of structure--property and structure--activity correlations

Journal Article · · Int. J. Quant. Chem., Symp.; (United States)

An exposition of a potentially useful graph-theoretical method for comparing structures is given. The concept of rigorous comparison of sequences, introduced into mathematics by Muirhead and generalized by Karamata, is applied to contributing terms in bond-additive schemes. Such an approach illuminates the origin for occasional deviations in the trends for structure--property and structure--activity correlations. The method is illustrated on the trends of boiling points and heats of vaporizations in hexane and heptane isomers and the corresponding trends for molecular connectivity indices of the molecules considered. The outlined concept of comparability of structures not only clarifies a posteriori occasional discrepancies in correlations, but may also a priori suggest circumstances when one cannot expect simple bond additivity. With the help of the comparability tests the empirical curve-fitting procedures no longer need be based on guessing, intuition, and analogy, since necessity for additional parameters in such schemes can be assessed in advance. 2 figures, 8 tables.

Research Organization:
Ames Lab., IA
OSTI ID:
6206978
Journal Information:
Int. J. Quant. Chem., Symp.; (United States), Vol. 5
Country of Publication:
United States
Language:
English