QSPR modeling of critical properties of organic binary mixtures

Abstract

QSPR models for the critical temperatures, critical volumes, and critical pressures of binary organic mixtures are given. The binary organic mixtures have been described in terms of the mixture modification of simplex representation of molecular structure. The accuracy of the obtained models is comparable to the recommended one, the mean error ranging from 6.8 to 14.6%. The models imply that electronic polarizability is the most important factor for the critical volume and that the critical temperature and critical pressure are determined primarily by van der Waals and electrostatic interactions.Critical properties of substances are important not only for understanding fundamental principles of their thermodynamic behavior but also from the application viewpoint since most methods for predicting unknown properties of compounds utilize the principle of corresponding states, which is based on critical parameters. Critical points exist not only for pure substances but also for their mixtures, and they determine stability parameters of mixtures, i.e., the transition from a heterogeneous mixture (phase boundary) to a homogeneous solution (single phase) [1].

Simplex representation of molecular structure as universal QSAR/QSPR tool

“…The development of QSPR models to predict the critical properties of mixtures of organic compounds [ 80 ] has no analogues. It was possible due to the use of special SiRMS descriptors aimed at describing mixtures of compounds (see the “ Simplex descriptors for solving various QSAR/QSPR tasks ” section).…”

“…Lipophilicity and water solubility [44], [66][67][68][69][70][71][72] Luminescent properties [73] Thermodynamic properties [74][75][76][77][78][79][80] Properties of ionic compounds and materials [81], [82] Properties of nanosystems [63], [83], [84] The concept of chiral simplexes helped us to understand these problems. As a mathematical object, a simplex is a ndimensional polyhedron, which is a convex shell (n+1) of points (vertexes of simplex) that do not lie in the (n-1)-dimensional plane [85].…”

“…A series of publications where SiRMS descriptors were used to build QSPR models were devoted to the thermodynamic properties of substances: the boiling temperatures, critical parameters, second virial coefficients, and adsorption parameters [74][75][76][77][78][79][80]. What distinguished these publications from other similar works was the demonstration of applications to mixtures of compounds (SiRMS for mixtures is described in the "Simplex descriptors for solving various QSAR/QSPR tasks" section.).…”

Quantitative structure–property relationship for the critical temperature of saturated monobasic ketones, aldehydes, and ethers with molecular descriptors

“…The QSPR approach has been applied to forecast many physicochemical properties, such as normal boiling point [3–5], thermal conductivity [6], retention time [7], critical micelle concentration (CMC) [8], standard enthalpies [9], toxicity degree [10], lower flammability limits [11], piC50 [12] and logP [13], and so forth. In the past 30 years, the relationship between the critical temperature and molecular descriptors of compounds has aroused widespread interest among chemists [14–24].…”