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The process of crystallization separation of an industrial mixture of perfluorinated cycloalkanes was considered. The content of target products, cis- and trans-isomers of perfluorodecalin (PFD), in all initial fractions of the investigated samples of the reaction mixture was at least 70 wt.%. Based on the experimental data, the dependences of the crystallization (partition) coefficients between the solid and mother liquor ( D s / l ), the enrichment factor (ηs), and the separation factor (Fs) on the ratio of trans-PFD to cis-PFD, the ratio of mother liquor to solid, and crystallization temperature in the range −50–15 °C were obtained. It was shown that the values D s / l and ηs depended significantly on the concentration of trans-PFD in the initial solution, and that the value of Fs decreased as the process temperature rose. [ABSTRACT FROM AUTHOR]

The process of crystallization separation of an industrial mixture of perfluorinated cycloalkanes was considered. The content of target products, cis- and trans-isomers of perfluorodecalin (PFD), in all initial fractions of the investigated samples of the reaction mixture was at least 70 wt.%. Based on the experimental data, the dependences of the crystallization (partition) coefficients between the solid and mother liquor (Ds/l), the enrichment factor (ηs), and the separation factor (Fs) on the ratio of trans-PFD to cis-PFD, the ratio of mother liquor to solid, and crystallization temperature in the range −50–15 °C were obtained. It was shown that the values Ds/l and ηs depended significantly on the concentration of trans-PFD in the initial solution, and that the value of Fs decreased as the process temperature rose.

Density functional theory (DFT) and Hartree–Fock (HF) methods have been used to calculate the electronic and geometric structures of cis- and trans-[Pt(NH3)2X2] (X = Cl-, Br-, I-), [cis-Pt(NH3)2(H2O)2]2+ and its deprotonated forms. The thermodynamic parameters ΔH0298, ΔS0298, ΔG0298, and ΔCp = f(T) have been obtained from DFT force fields and normal mode frequencies. It is shown that the greater stability of the trans-isomers is due, at the molecular level, to different interligand interactions. The stability of the cis-isomers is significantly increased by intermolecular Pt…Pt and NH2-H…X nonvalence interactions between mononuclear [cis-Pt(NH3)2X2] moieties, the effect reducing in the row Cl- > Br- > I-. The thermodynamic parameters of possible phases of the hydrolysis of [cis-Pt(NH3)2(H2O)2]2+ have been also derived. Solvent effects have been investigated calculating the equilibrium constants for the proton transfer reactions both in gas phase and water solution. It is shown that in aqueous medium the hydroxobridged platinum dimer [Pt(NH3)2- (μ-OH)]2+2, characterized by a Pt…Pt distance of 3.119 Å, is the preferred hydrolysis product. It is also shown that with short metal–metal interactions, such as those found in [cis-Pt(NH3)2Cl2] and [cis-Pt(NH3)2(H2O)2]2+, the conditions for the formation of linear polynuclear complexes with Pt—Pt bonds (the so-called “platinum blues”) are created. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004 [ABSTRACT FROM AUTHOR]