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  • Author or Editor: P. Semyannikov x
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Abstract  

The temperature dependency of the saturated vapor pressure of Ir(acac)3 has been measured by the method of calibrated volume (MCV), the Knudsen method, the flow transpiration method, and the membrane method. The thermodynamic parameters of phase transition of a crystal to gas were calculated using each of these methods, and the following values of ΔH T 0 (kJ mol−1) and ΔS T 0 (J mol−1K−1), respectively, were obtained: MCV: 101.59, 156.70; Knudsen: 130.54, 224.40; Flow transpiration: 129.34, 212.23; Membrane: 95.45, 149.44 Coprocessing of obtaining data (MCV, flow transportation method and Knudsen method) at temperature ranges 110−200C as also conducted:ΔH T 0 =127.92.1 (kJ mol−1 ); ΔS T 0 =215.25.0 (J mol−1 K−1 ).

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Abstract  

The thermal decomposition of several lanthanide salts Ln(CF3COO)33H2O (Ln=La, Gd, Tb) was studied under quasi-equilibrium conditions and under linear heating. According to mass spectral data, H2O is the single product of thermal decomposition up to 120-140C. Thermogravimetric data were processed with 'Netzsch Thermokinetics' computer program. Kinetics parameters of the first decomposition step (as the simple dehydration process, not complicated by the water hydrolysis with the liberation or the decomposition of the organic ligand) were calculated.

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Abstract  

Complexes of ruthenium(III) with the following beta-diketones: 2,4-pentanedione (Ru(acac)3), 1,1,1-trifluoro-2,4-pentanedione (Ru(tfac)3), 2,2,6,6-tetramethyl-3,5-heptanedione (Ru(thd)3), 2,2,6,6–tetramethyl-4-fluoro-3,5-heptanedione (Ru(tfhd)3) and 1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedione (Ru(ptac)3) were synthesized and identified by means of mass spectrometry. By effusion Knudsen method with mass spectrometric registration of gas phase composition the temperature dependencies of saturated vapor pressure were measured for ruthenium(III) compounds and the thermodynamic characteristics of vaporization processes enthalpy ΔH T* and entropy
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\Updelta S^{\text{o}}_{T*}$$ \end{document}
of this complexes were determined.
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Abstract  

Volatile compounds of iridium(I): (acetylacetonato)(1,5-cyclooctadiene)iridium(I) Ir(acac)(cod), (methylcyclopentadienyl) (1,5-cyclooctadiene)iridium(I) Ir(Cp’)(cod), (pentamethylcyclopentadienyl)(dicarbonyl) iridium(I) Ir(Cp*)(CO)2 and (acetylacetonato)(dicarbonyl)iridium(I) Ir(acac)(CO)2 were synthesized and identified by means of element analysis, NMR-spectroscopy, mass spectrometry. Thermal properties in solid phase for synthesized iridium(I) complexes were studied by means of thermogravimetric analysis in inert atmosphere (He). By effusion Knudsen method with mass spectrometric registration of gas phase composition the temperature dependencies of saturated vapor pressure were measured for iridium(I) compounds and the thermodynamic characteristics of vaporization processes enthalpy ΔH T* and entropy ΔS T 0 were determined. The energy of intermolecular interaction in the crystals of complexes was calculated.

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Journal of Thermal Analysis and Calorimetry
Authors: E. Filatov, S. Sysoev, Ludmila Zelenina, Tamara Chusova, V. Logvinenko, P. Semyannikov, and I. Igumenov

Abstract  

Thermal behaviour of a series of lithium β-diketonates: Li(dpm) (dpm=dipivaloylmethanate (2,2,6,6-tetramethylheptane-3,5- dionate)), Li(pta) (pta=pivaloyltrifluoracetonate (2,2-dimethyl-6,6,6-trifluoro-3,5-hexanedionate)), Li(tfa) (tfa=trifluoracetylacetonate (1,1,1-trifluoro-2,4-pentandionate)), Li(hfa) (hfa=hexafluoracetylacetonate (1,1,1,5,5,5-hexafluoro-2,4-pentandionate)) has been investigated. Gas phase composition of these complexes has been established. Temperature dependences of vapor pressure of lithium compounds were obtained by static and dynamic methods, and thermodynamic parameters were calculated. Dependence of compound volatility on ligand structure is shown. For Li(dpm) detailed investigation has been done by differential scanning calorimetry (DSC).

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Journal of Thermal Analysis and Calorimetry
Authors: A. Bessonov, N. Morozova, P. Semyannikov, S. Trubin, N. Gelfond, and I. Igumenov

Abstract  

The thermal properties of dimethylgold(III) carboxylates of general formula [(CH3)2Au(OOCR)]2 (R=methyl (1), tert-buthyl (2), trifluoromethyl (3), or phenyl (4)) in solid state have been investigated by the thermogravimetric analysis. The temperature dependences of saturated vapour pressure of complexes have been studied by the Knudsen effusion method with mass spectrometric indication. The thermodynamic parameters Δsub H T 0 and Δsub S T 0 of the sublimation processes have been calculated. Thermal decomposition of the vapour of complexes 1 and 2 has been studied by means of high temperature mass spectrometry in vacuum, and by-products of decomposition have been determined.

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Abstract  

A thermoanalytical study of the diethyldithiocarbamates of the platinum metals Pt(II), Pd(II), Rh(III), Ir(III) and Ru(III) was carried out by means of DTA techniques in an inert atmosphere and in vacuum. Decomposition temperatures were determined and the mass loss curves were obtained for these compounds in helium and in vacuum. The X-ray diffraction patterns of the solid products of M(dtk)n thermolysis were studied. The temperature dependences of the saturated vapour pressures of the listed chelates were measured by flow and Knudsen methods, and the vaporization parameters were determined.

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