Descriptor of a Structure–Property Model for Calculating the Critical Temperature of a Liquid–Vapor Phase Transition with the Topological Characteristics of Alkene Molecules

A nonlinear multidimensional model is proposed for calculating the critical temperature of normal and substituted alkenes through the topological characteristics of molecular graphs, i.e., the Randić index and an index that allows for differences in cis and trans isomers and eigenvalue functions of the topological matrix of a molecule. A three-parameter QSPR model descriptor is obtained that adequately describes the critical temperature of alkenes for the liquid–vapor phase transition. The average absolute error of the critical temperature for a number of alkenes from 51 compounds is found to be 4.7. It is concluded that the proposed model can be used to calculate critical temperatures in chemical technology and power engineering.