Samarium selenates

Suponitskii et al. [69SUP/MA1] determined the enthalpy change of the reaction between Sm2(Se04)3-8H20(cr) and a solution of barium chloride with formation of BaSe04(cr) by a calorimetric measurement. The review calculated the enthalpy of formation  

No other thermodynamic data have been found for samarium selenates. 

The anhydrous compound is formed by heating NH4Sm(Se04)2-4H20 to 500°C (TG), corresponding to a DTA peak at 470°C it decomposes after dehydration, Nabar, Paralkar [1]. 

The enthalpy of formation of the crystalline compound is AH298=-1306.0 kcal/mol, Schumm et al. [5]. The salt is less soluble in hot than in cold water. The octahydrate separates from aqueous solutions at all temperatures between 10 and 100°C and is stable in dry air. Solubility S in wt% anhydrous Sm2(Se04)3 (selected values)  

The values for the Nd2(Se04)3-5H20-based mixed crystal are read from a figure in the paper. 

Theoretical calculated values for AH ix are given in the paper, Serebrennikov et al. [4]. The system was also studied at 25°C by Tsybukova [8]. 

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The 4,7-dimethoxy-2,2-dimethyl-l,3,2-benzodiselenastannole 321 was prepared from commercially available 1,4-dimethoxybenzene 320 by a sequence of tandem ortho-lithiation and selenation, and followed by dimethyltin protection in 28% yield (Scheme 51). Then, sequential treatment of the stannole 321 in THF with selenyl chloride, trimethylsilyl trifluoromethanesulfonate (TMSOTf), and samarium iodide gave crystalline 4,7-dimethoxybenzotri-selenole 42 in 75% yield <1996H(43)1843>. The structure was characterized by X-ray crystallographic analysis (Section 6.12.3.1). 

Samarium (III) nitrate, analysis of anhydrous, 6 41 Selenic acid, crystalline, 3 137 Selenides, precipitation of pure metallic, from solutions of hydrogen selenide, 2 185 Selenium, red and gray, 1 119 Selenium (II) chloride, formation of, by selenium(IV) chloride, 6 127... 

K., Doroshenko, N. A., Karapet yants, M. K., Enthalpy of formation of selenates of praseodymium, neodymium, and samarium, Russ. J. Phys. Chem., 43, (1969), 711. From a citation in this Bibliography... 

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