A novel topological index for the studies on structure-properties of alkanes

A novel topological index derived from eccentric connectivity index has been proposed. The new topological index and eccentric connectivity index were correlated with eight physical properties such as the boiling point, critical temperature, critical pressure, critical volume, evaporation heat, density, heat capacity, surface tension, and three thermodynamic properties such as standard enthalpy, standard entropy and standard formation free energy of alkanes. A series of empiric equations for calculating the properties were obtained. Correlation coefficients of nine properties were more than 0.99. Regression analysis and calculation results indicated that the topological indices were well correlated with the physico-chemical properties of alkanes, and the novel topological index was far superior to eccentric connectivity index in the correlation. Foundation item: Supported by the Natural Science Fund of Hubei Educational Committee (99A088) Biography: Ni Cai-hua (1956-), male, Professor, research direction: organic chemistry and Polymer.