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Abstract  

The standard enthalpies of formation of alkaline metals thiolates in the crystalline state were determined by reaction-solution calorimetry. The obtained results at 298.15 K were as follows:
\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} $$\Updelta_{\text{f}} H_{\text{m}}^{\text{o}} ({\text{MSR,}}\;{\text{cr}})$$ \end{document}
/kJ mol−1 = −259.0 ± 1.6 (LiSC2H5), −199.9 ± 1.8 (NaSC2H5), −254.9 ± 2.4 (NaSC4H9), −240.6 ± 1.9 (KSC2H5), −235.8 ± 2.0 (CsSC2H5). These results where compared with the literature values for the corresponding alkoxides and together with values for
\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} $$\Updelta_{\text{f}} H_{\text{m}}^{\text{o}} \left( {{\text{MSH}},\;{\text{cr}}}\right)$$ \end{document}
were used to derive a consistent set of lattice energies for MSR compounds based on the Kapustinskii equation. This allows the estimation of the enthalpy of formation for some non-measured thiolates.
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Journal of Thermal Analysis and Calorimetry
Authors: Ricardo Simões, Ana Aleixo, Ana Lagoa, Manuel Minas da Piedade, João Leal, Thorsten Peitsch, and Matthias Epple

Abstract  

A thermoanalytical, morphological, and structural study of fluoridated calcium phosphates that were prepared by different variants of a synthesis in anhydrous alcohols is reported. The obtained materials were neither fully amorphous nor single-phased crystalline, and their nature considerably depended on the synthesis conditions. In all cases, the retention of significant amounts of solvent in the solid product was observed. A complete removal of the solvent was only possible by heating to temperatures above ~573–673 K which resulted in variations in the elemental composition, phase changes, and an increase of the crystallinity. Consequently, this synthesis in anhydrous alcohols is not a viable route to obtain materials with a defined crystallinity and stoichiometry.

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