Thorium(IV) chloride

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Thorium(IV) chloride
3D model (JSmol)
ECHA InfoCard 100.030.039 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 233-056-1
PubChem CID
RTECS number
  • XO6475000
  • InChI=1S/4ClH.Th/h4*1H;/q;;;;+4/p-4
  • Cl[Th](Cl)(Cl)Cl
Molar mass 373.849 g/mol
Appearancewhite needles
Density 4.59 g/cm3, solid
Melting point 770 °C (1,420 °F; 1,040 K)
Boiling point 921 °C (1,690 °F; 1,194 K)
Lethal dose or concentration (LD, LC):
332 mg/kg intraperitoneal mouse
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Thorium(IV) chloride describes a family of inorganic compounds with the formula ThCl4(H2O)n. Both the anhydrous and tetrahydrate (n = 4) forms are known. They are hygroscopic, water-soluble white salts.



Alternative view of the structure of solid ThCl4. Kristallstruktur Uran(IV)-fluorid.png
Alternative view of the structure of solid ThCl4.

The structure of thorium(IV) chloride features 8-coordinate Th centers with doubly bridging chloride ligands. [1]


ThCl4 was an intermediate in the original isolation of thorium metal by Jons Jacob Berzelius. [2]

Thorium(IV) chloride can be produced in a variety of ways. One method is a carbothermic reaction, 700 °C to 2600 °C, involving thorium oxides and carbon in a stream of chlorine gas:

ThO2 + 2 C + 4 Cl2 → ThCl4 + 2 CO

The chlorination reaction can be effected with carbon tetrachloride: [3] [4]

Th(C2O4)2 + CCl4 → ThCl4 + 3 CO + 3 CO2

In another two-step method, thorium metal reacts with ammonium chloride:

Th + 6 NH4Cl → (NH4)2ThCl6 + 4 NH3 + 2 H2

The hexachloride salt is then heated at 350 °C under a high vacuum to produce ThCl4. [5]


Lewis base adducts

ThCl4 reacts with Lewis bases to give molecular adducts, such as ThCl4(DME)2 and ThCl4(TMEDA)2. [5]

Reduction to Th metal

Thorium(IV) chloride is an intermediate in the purification of thorium, which can be affected by:

  1. Reduction of ThCl4 with alkali metals.
  2. Electrolysis of anhydrous thorium(IV) chloride in fused mixture of NaCl and KCl.
  3. Ca reduction of a mixture of ThCl4 with anhydrous zinc chloride. [6]

Related Research Articles

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Protactinium is a chemical element; it has symbol Pa and atomic number 91. It is a dense, radioactive, silvery-gray actinide metal which readily reacts with oxygen, water vapor, and inorganic acids. It forms various chemical compounds, in which protactinium is usually present in the oxidation state +5, but it can also assume +4 and even +3 or +2 states. Concentrations of protactinium in the Earth's crust are typically a few parts per trillion, but may reach up to a few parts per million in some uraninite ore deposits. Because of its scarcity, high radioactivity, and high toxicity, there are currently no uses for protactinium outside scientific research, and for this purpose, protactinium is mostly extracted from spent nuclear fuel.

<span class="mw-page-title-main">Silicon tetrachloride</span> Chemical compound

Silicon tetrachloride or tetrachlorosilane is the inorganic compound with the formula SiCl4. It is a colorless volatile liquid that fumes in air. It is used to produce high purity silicon and silica for commercial applications. It is a part of the chlorosilane family.

Iron(III) chloride describes the inorganic compounds with the formula FeCl3(H2O)x. Also called ferric chloride, these compounds are some of the most important and commonplace compounds of iron. They are available both in anhydrous and in hydrated forms which are both hygroscopic. They feature iron in its +3 oxidation state. The anhydrous derivative is a Lewis acid, while all forms are mild oxidizing agent. It is used as a water cleaner and as an etchant for metals.

Sulfur trioxide (alternative spelling sulphur trioxide, also known as nisso sulfan) is the chemical compound with the formula SO3. It has been described as "unquestionably the most important economically" sulfur oxide. It is prepared on an industrial scale as a precursor to sulfuric acid.

<span class="mw-page-title-main">Zinc chloride</span> Chemical compound

Zinc chloride is the name of inorganic chemical compounds with the formula ZnCl2. It forms hydrates. Zinc chloride, anhydrous and its hydrates are colorless or white crystalline solids, and are highly soluble in water. Five hydrates of zinc chloride are known, as well as four forms of anhydrous zinc chloride. This salt is hygroscopic and even deliquescent. Zinc chloride finds wide application in textile processing, metallurgical fluxes, and chemical synthesis. No mineral with this chemical composition is known aside from the very rare mineral simonkolleite, Zn5(OH)8Cl2·H2O.

<span class="mw-page-title-main">Titanium tetrachloride</span> Inorganic chemical compound

Titanium tetrachloride is the inorganic compound with the formula TiCl4. It is an important intermediate in the production of titanium metal and the pigment titanium dioxide. TiCl4 is a volatile liquid. Upon contact with humid air, it forms thick clouds of titanium dioxide and hydrochloric acid, a reaction that was formerly exploited for use in smoke machines. It is sometimes referred to as “tickle” or “tickle 4”, as a phonetic representation of the symbols of its molecular formula.

Tin(IV) chloride, also known as tin tetrachloride or stannic chloride, is an inorganic compound with the formula SnCl4. It is a colorless hygroscopic liquid, which fumes on contact with air. It is used as a precursor to other tin compounds. It was first discovered by Andreas Libavius (1550–1616) and was known as spiritus fumans libavii.

<span class="mw-page-title-main">Nickel(II) chloride</span> Chemical compound

Nickel(II) chloride (or just nickel chloride) is the chemical compound NiCl2. The anhydrous salt is yellow, but the more familiar hydrate NiCl2·6H2O is green. Nickel(II) chloride, in various forms, is the most important source of nickel for chemical synthesis. The nickel chlorides are deliquescent, absorbing moisture from the air to form a solution. Nickel salts have been shown to be carcinogenic to the lungs and nasal passages in cases of long-term inhalation exposure.

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<span class="mw-page-title-main">Hafnium tetrachloride</span> Chemical compound

Hafnium(IV) chloride is the inorganic compound with the formula HfCl4. This colourless solid is the precursor to most hafnium organometallic compounds. It has a variety of highly specialized applications, mainly in materials science and as a catalyst.

<span class="mw-page-title-main">Phosphoryl chloride</span> Chemical compound

Phosphoryl chloride is a colourless liquid with the formula POCl3. It hydrolyses in moist air releasing phosphoric acid and fumes of hydrogen chloride. It is manufactured industrially on a large scale from phosphorus trichloride and oxygen or phosphorus pentoxide. It is mainly used to make phosphate esters such as tricresyl phosphate.

Boron trichloride is the inorganic compound with the formula BCl3. This colorless gas is a reagent in organic synthesis. It is highly reactive toward water.

<span class="mw-page-title-main">Zirconium(IV) chloride</span> Chemical compound

Zirconium(IV) chloride, also known as zirconium tetrachloride, is an inorganic compound frequently used as a precursor to other compounds of zirconium. This white high-melting solid hydrolyzes rapidly in humid air.

<span class="mw-page-title-main">Uranium tetrachloride</span> Chemical compound

Uranium tetrachloride is an inorganic compound, a salt of uranium and chlorine, with the formula UCl4. It is a hygroscopic olive-green solid. It was used in the electromagnetic isotope separation (EMIS) process of uranium enrichment. It is one of the main starting materials for organouranium chemistry.

<span class="mw-page-title-main">Organoactinide chemistry</span> Study of chemical compounds containing actinide-carbon bonds

Organoactinide chemistry is the science exploring the properties, structure, and reactivity of organoactinide compounds, which are organometallic compounds containing a carbon to actinide chemical bond.

<span class="mw-page-title-main">Niobium(IV) chloride</span> Chemical compound

Niobium(IV) chloride, also known as niobium tetrachloride, is the chemical compound of formula NbCl4. This compound exists as dark violet crystals, is highly sensitive to air and moisture, and disproportiates into niobium(III) chloride and niobium(V) chloride when heated.

<span class="mw-page-title-main">Lead(IV) chloride</span> Chemical compound

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<span class="mw-page-title-main">Titanium(IV) nitrate</span> Chemical compound

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Hafnium compounds are compounds containing the element hafnium (Hf). Due to the lanthanide contraction, the ionic radius of hafnium(IV) (0.78 ångström) is almost the same as that of zirconium(IV) (0.79 angstroms). Consequently, compounds of hafnium(IV) and zirconium(IV) have very similar chemical and physical properties. Hafnium and zirconium tend to occur together in nature and the similarity of their ionic radii makes their chemical separation rather difficult. Hafnium tends to form inorganic compounds in the oxidation state of +4. Halogens react with it to form hafnium tetrahalides. At higher temperatures, hafnium reacts with oxygen, nitrogen, carbon, boron, sulfur, and silicon. Some compounds of hafnium in lower oxidation states are known.


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  2. Weeks, Mary Elvira (1932-07-01). "The Discovery of the Elements. XI. Some Elements Isolated with the Aid of Potassium and Sodium: Zirconium, Titanium, Cerium, and Thorium". Journal of Chemical Education. 9 (7): 1231. Bibcode:1932JChEd...9.1231W. doi:10.1021/ed009p1231. ISSN   0021-9584.
  3. Brauer, Georg (1963). Handbook Of Preparative Inorganic Chemistry. New York: Academic Press.
  4. Gutierrez, R. L.; Herbst, R. J. (October 1979). "Preliminary Fabrication Studies of Alternative LMFBR Carbide Fuels". Los Alamos Scientific Laboratory. doi:10.2172/5688597.
  5. 1 2 Cantat, Thibault; Scott, Brian L.; Kiplinger, Jaqueline L. (2010-01-25). "Convenient Access to the Anhydrous Thorium Tetrachloride Complexes ThCl4(DME)2, ThCl4(1,4-dioxane)2 and ThCl4(THF)3.5 using Commercially Available and Inexpensive Starting Materials". Chemical Communications. 46 (6): 919–21. doi:10.1039/b923558b. ISSN   1364-548X. PMID   20107650.
  6. "Periodic Table of Elements: Los Alamos National Laboratory". Retrieved 2016-04-29.