(153c) A Quantum Structure Property Relationship Based Approach for Computing Critical Properties, Heat of Vaporization and Gas-Phase Transport Parameters of Pure Components

A method has been developed, based Quantum Structure Property Relationships (QSPR), to predict various physical properties of pure components. These properties include critical temperature, pressure, volume, temperature dependent heat of vaporization, Lennard-Jones volume and potential, and molecular polarizability. The method is based on single molecule ab-initio quantum chemistry, and descriptors derived from the CosmoTherm software package. QSPR correlations were developed using 5 to 7 molecular descriptors, a diverse set of 80 to 150 molecules, and validated on another set of 200 to 700 molecules depending on availability of experimental data of the given property. The used molecular descriptors are related to the size of a molecule, symmetry, apolarity, polarity, H-bond acceptor and donor properties. As the developed QSPR correlations based on small number of descriptors are suitable for extrapolations, consistent set of properties can be derived not only for stable molecules, but also that of high reactivity ? such as radicals, which are hard to estimate by other methods.