Hexaperchloratoaluminate

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The hexaperchloratoaluminate ion is a polyatomic anion with the chemical formula [ Al(Cl O 4)6]3−. It is composed of six perchlorate (ClO4) anions bound to a central aluminium ion (Al3+), resulting in a net charge of –3. This ion is a highly oxidizing and reactive complex, similar to other hexacoordinate aluminium complexes such as hexanitratoaluminate.

The aluminium perchlorate salts formed with hexaperchloratoaluminate are of particular interest due to their potential uses as energetic materials. The series of hexaperchloratoaluminate salts includes lithium hexaperchloratoaluminate, ammonium hexaperchloratoaluminate, tetramethylammonium hexaperchloratoaluminate, and trinitronium hexaperchloratoaluminate. Each of these compounds possess unique properties and may have potential applications in areas such as rocket propellants, pyrotechnics, and other explosive-based technologies. [1]

Preparation

Hexaperchloratoaluminates can be synthesized by combining aluminum trichloride and various perchlorates in liquid sulfur dioxide at a temperature of –10°C: [1]

3 [NO2]ClO4 + 3 LiClO4 + AlCl3 → 3 NO2Cl + Li3[Al(ClO4)6],
3 [NO2]ClO4 + 3 [NH4]ClO4 + AlCl3 → 3 NO2Cl + [NH4]3[Al(ClO4)6],
6 [NO2]ClO4 + AlCl3 → 3 NO2Cl + [NO2]3[Al(ClO4)6].

To form hexaperchloratoaluminates, one can heat aluminium nitrate in the presence of nitrosonium or nitronium perchlorate at a temperature of 125 °C: [1]

10–14 [NO]ClO4 + Al(NO3)3 → [NO2]3[Al(ClO4)6] + (gaseous products),
6–10 [NO2]ClO4 + Al(NO3)3 → [NO2]3[Al(ClO4)6] + (gaseous products),
3 [NO2]ClO4 + 3 KClO4 + AlCl3 → 3 NO2Cl + K3[Al(ClO4)6].

Obtaining hydrazinium hexaperchloratoaluminate in a highly pure form is problematic. According to the available studies, this compound can only be produced via a low-yielding synthesis route including the reaction of aluminium chloride, hydrazinium perchlorate, and nitronium perchlorate: [1]

3 [NO2]ClO4 + 3 [N2H5]ClO4 + AlCl3 → 3 NO2Cl + [N2H5]3[Al(ClO4)6].

Guanidinium hexaperchloratoaluminate can be synthesized via the following reaction: [1]

3 [NO2]ClO4 + 3 [C(NH2)3]ClO4 + AlCl3 → 3 NO2Cl + [C(NH2)3]3[Al(ClO4)6].

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The chemical element nitrogen is one of the most abundant elements in the universe and can form many compounds. It can take several oxidation states; but the most common oxidation states are -3 and +3. Nitrogen can form nitride and nitrate ions. It also forms a part of nitric acid and nitrate salts. Nitrogen compounds also have an important role in organic chemistry, as nitrogen is part of proteins, amino acids and adenosine triphosphate.

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<span class="mw-page-title-main">Dichlorine hexoxide</span> Chemical compound

Dichlorine hexoxide is the chemical compound with the molecular formula Cl
2
O
6
, which is correct for its gaseous state. However, in liquid or solid form, this chlorine oxide ionizes into the dark red ionic compound chloryl perchlorate [ClO
2
]+
[ClO
4
]
, which may be thought of as the mixed anhydride of chloric and perchloric acids.

Perchloratoborate is an anion of the form [B(ClO4)4]. It can form partly stable solid salts with heavy alkali metals. They are more stable than nitratoborate salts. K[B(ClO4)4] decomposes at 35 °C, Rb[B(ClO4)4] is stable to 50 °C, and Cs[B(ClO4)4] can exist up to 80 °C.

Tetraperchloratoaluminates are salts of the tetraperchloratoaluminate anion, [Al(ClO4)4]. The anion contains aluminium tetrahedrally surrounded by four perchlorate groups. The perchlorate is covalently bonded to the aluminium, but perchlorate is much more well known as an ion. The covalent bond to aluminium distorts the perchlorate and renders it unstable.

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

Tetranitratoaluminate is an anion of aluminium and nitrate groups with formula [Al(NO3)4] that can form salts called tetranitratoaluminates. It is unusual in being a nitrate complex of a light element.

Hexanitratoaluminate is an anion of aluminium and six nitrate groups with formula [Al(NO3)6]3− that can form salts called hexanitratoaluminates.

Zirconium perchlorate is a molecular substance containing zirconium and perchlorate groups with formula Zr(ClO4)4. Zr(ClO4)4 is a volatile crystalline product. It can be formed by reacting zirconium tetrachloride with dry perchloric acid at liquid nitrogen temperatures. Zr(ClO4)4 sublimes slowly in a vacuum at 70°C showing that the molecule is covalently bound rather than being ionic. The reaction also forms some zirconyl perchlorate (or zirconium oxyperchlorate) ZrO(ClO4)2 as even apparently pure perchloric acid is in equilibrium with dichlorine heptoxide, hydronium ions and perchlorate ions. This side product can be minimised by adding more dichlorine heptoxide or doing the reaction as cold as possible.

Cobalt compounds are chemical compounds formed by cobalt with other elements.

Gallium compounds are compounds containing the element gallium. These compounds are found primarily in the +3 oxidation state. The +1 oxidation state is also found in some compounds, although it is less common than it is for gallium's heavier congeners indium and thallium. For example, the very stable GaCl2 contains both gallium(I) and gallium(III) and can be formulated as GaIGaIIICl4; in contrast, the monochloride is unstable above 0 °C, disproportionating into elemental gallium and gallium(III) chloride. Compounds containing Ga–Ga bonds are true gallium(II) compounds, such as GaS (which can be formulated as Ga24+(S2−)2) and the dioxan complex Ga2Cl4(C4H8O2)2. There are also compounds of gallium with negative oxidation states, ranging from -5 to -1, most of these compounds being magnesium gallides (MgxGay).

References

  1. 1 2 3 4 5 Guibert, C. R.; A. D. McElroy (10 Feb 1964). "Annual Report Studies of Complex Perchlorates". Callery Chemical Company. pp. 5–7. Archived from the original on March 3, 2016. Retrieved 3 October 2014.