Thorium tetrachloride

Several methods are available for producing thorium metal it can be obtained by reducing thorium oxide with calcium, by electrolysis of anhydrous thorium chloride in a fused mixture of sodium and potassium chlorides, by calcium reduction of thorium tetrachloride mixed with... 

The last reaction is the most favored of these three. The actual occurrence of the reactions with elemental phosphorus or phosphorous trichloride as products has been explained to be due to kinetic reasons. The thorium present in the ore volatilizes in the form of thorium tetrachloride (ThCl4) vapor other metallic impurities such as iron, chromium, aluminum, and titanium also form chlorides and vaporize. The product obtained after chlorination at 900 °C is virtually free from thorium chloride and phosphorous compounds, and also from the metals iron, aluminum, chromium, and titanium. 

The preparation of U(CsH5)2Cl2 91) and U(C5Hs)Cl3 -DME 92) were reported shortly after thallium(I) cyclopentadienide was found to be useful in controlhng the stoichiometries of reactions with uranium and thorium tetrachloride 93, 94). 

J. L. Gay Lussac and L. J. Thenard 5 showed in 1811 that if many of the metallic oxides be intimately mixed with carbon the reaction with chlorine proceeds more readily than with the oxide alone the metal chloride and carbon monoxide or dioxide are the products of the reaction. M. le Quesneville and F. Wohler used this process for aluminium chloride, chromic chloride, silicon tetrachloride, etc., and C. Baskerville for thorium tetrachloride. 

ThCl4 (c). For the heat of solution of solid thorium tetrachloride in water, Chauvenet2 found 56.7 at 15° and von Wartenberg 53. For the heat of formation of ThCl4 (c) by direct synthesis from a very impure sample of thorium, von Wartenberg6 reported Q/=300. 

PROP White, odorless crystals or deliquescent, white solid. D 4.59, mp 770°, bp 928°. Sol in water (with hydrol) and ale. SYNS TETRACHLOROTHORIUM THORIUM TETRACHLORIDE... 

The actinide tetrachloride-DMSO complexes are particularly interesting (18). There is a pronounced change in stability proceeding along the actinide series with 1 5 complexes being the most stable for thorium and protactinium and the 1 3 complexes for the remaining actinides. The 1 7 complex could not be obtained pure with thorium tetrachloride and under the preparative conditions required, namely, recrystallization from hot dimethyl sulfoxide, protactinium(IV) was oxidized. The solid 1 5 and 1 3 protactinium tetrachloride compounds are, in fact, unstable in dry nitrogen, behavior which contrasts markedly with the stability of the tetrahalide-phosphine oxide and DMA complexes. 

Tetrachloride and tetrabromide complexes are known for thorium, protactinium, uranium, neptunium, and plutonium. These are similarly produced by halide-based oxidation of metals or hydrides, or by halogenation of oxides. A common structural type is reported for most compounds. The reported structure of thorium tetrachloride reveals that the coordination geometry about the metal is dodecahedral.The compounds are generally volatile and can be sublimed. The gas-phase electron diffraction structure of suggests that the molecule is... 

Thus the structures of tetrakis(N-isopropyl-3,3-dimethylbutano-and -2,2-dimethylpropano)hydroxamatothorium(IV) have been determined by single crystal X-ray diffraction (77). Keeping the pH as low as possible, these compounds precipitate upon the addition of an aqueous solution of thorium tetrachloride to an aqueous solution of the sodium salt of the hydroxamic acid. The analogous uranium(IV) complexes were prepared similarly under an inert atmosphere using deaerated solvents. In addition to their hydrocarbon solubility, the bulky alkyl substituents impart other interesting properties to these complexes. They melt at 127-8 and 116-7°C and, under a vacuum of 10 3 torr, sublime at 95 and 100°C, respectively ... 

A quinoline-soluble thorium phthalocyanine is formed in the reaction of thorium tetrachloride with phthalonitrile at 260°C 378), but no analytical data were reported. An ill-characterized sulfonated derivative has also been recorded 119). Uianyl phthalocyanine (U02Pc) has been observed as the product of the reaction of bis(dimethylformamide)uranyl acetate with dilithium phthalocyanine 119, 120), and of the reaction of uranyl acetate with phthalic anhydride 187, 233). Recently, however, Bloor et al. 31) reported that uranyl phthalocyanine formed by the reaction of uranyl chloride and phthalonitrile in dimethylformamide at 180°C has different infrared and visible absorption spectra from those originally quoted 187, 233) and they conclude, on the basis of infrared data, that the uranyl phthalocyanine obtained by previous workers was essentially a mixture of a metal-free phthalocyanine and inorganic uranium salts. 

TaCI3[g] TANTALUM TRICHLORIDE (GAS) 1597 fhCW THORIUM TETRACHLORIDE 1645... 

TaCI4 TANTALUM TETRACHLORIDE 1597 niCI4[g] THORIUM TETRACHLORIDE (GAS) 1646... 

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