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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<span class="mw-page-title-main">Nitronium ion</span> Polyatomic ion

The nitronium ion, [NO2]+, is a cation. It is an onium ion because its nitrogen atom has +1 charge, similar to ammonium ion [NH4]+. It is created by the removal of an electron from the paramagnetic nitrogen dioxide molecule NO2, or the protonation of nitric acid HNO3.

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

Perchloric acid is a mineral acid with the formula HClO4. Usually found as an aqueous solution, this colorless compound is a stronger acid than sulfuric acid, nitric acid and hydrochloric acid. It is a powerful oxidizer when hot, but aqueous solutions up to approximately 70% by weight at room temperature are generally safe, only showing strong acid features and no oxidizing properties. Perchloric acid is useful for preparing perchlorate salts, especially ammonium perchlorate, an important rocket fuel component. Perchloric acid is dangerously corrosive and readily forms potentially explosive mixtures.

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

Dinitrogen pentoxide is the chemical compound with the formula N2O5. It is one of the binary nitrogen oxides, a family of compounds that only contain nitrogen and oxygen. It exists as colourless crystals that sublime slightly above room temperature, yielding a colorless gas.

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

Aluminium chloride, also known as aluminium trichloride, is an inorganic compound with the formula AlCl3. It forms a hexahydrate with the formula [Al(H2O)6]Cl3, containing six water molecules of hydration. Both the anhydrous form and the hexahydrate are colourless crystals, but samples are often contaminated with iron(III) chloride, giving them a yellow colour.

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

Sodium perchlorate is an inorganic compound with the chemical formula NaClO4. It consists of sodium cations Na+ and perchlorate anions ClO−4. It is a white crystalline, hygroscopic solid that is highly soluble in water and ethanol. It is usually encountered as sodium perchlorate monohydrate NaClO4·H2O. The compound is noteworthy as the most water-soluble of the common perchlorate salts.

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

Ammonium nitrite is a chemical compound with the chemical formula [NH4]NO2. It is the ammonium salt of nitrous acid. It is composed of ammonium cations [NH4]+ and nitrite anions NO−2. It is not used in pure isolated form since it is highly unstable and decomposes into water and nitrogen, even at room temperature.

The nitrosonium ion is NO+, in which the nitrogen atom is bonded to an oxygen atom with a bond order of 3, and the overall diatomic species bears a positive charge. It can be viewed as nitric oxide with one electron removed. This ion is usually obtained as the following salts: NOClO4, NOSO4H (nitrosylsulfuric acid, more descriptively written ONSO3OH) and NOBF4. The ClO−4 and BF−4 salts are slightly soluble in acetonitrile CH3CN. NOBF4 can be purified by sublimation at 200–250 °C and 0.01 mmHg (1.3 Pa).

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

Iron(III) nitrate, or ferric nitrate, is the name used for a series of inorganic compounds with the formula Fe(NO3)3.(H2O)n. Most common is the nonahydrate Fe(NO3)3.(H2O)9. The hydrates are all pale colored, water-soluble paramagnetic salts.

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.

<span class="mw-page-title-main">Hexafluorophosphate</span> Anion with the chemical formula PF6–

Hexafluorophosphate is an anion with chemical formula of [PF6]. It is an octahedral species that imparts no color to its salts. [PF6] is isoelectronic with sulfur hexafluoride, SF6, and the hexafluorosilicate dianion, [SiF6]2−, and hexafluoroantimonate [SbF6]. In this anion, phosphorus has a valence of 5. Being poorly nucleophilic, hexafluorophosphate is classified as a non-coordinating anion.

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

Ammonium dinitramide (ADN) is an inorganic compound with the chemical formula [NH4][N(NO2)2]. It is the ammonium salt of dinitraminic acid HN(NO2)2. It consists of ammonium cations [NH4]+ and dinitramide anions N(NO2)2. ADN decomposes under heat to leave only nitrogen, oxygen, and water.

<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. This compound is a notable perchlorating agent.

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.

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).

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

Nitrosyl perchlorate is the inorganic compound with the formula NO(ClO4). A hygroscopic white solid, it is the salt of the nitrosonium cation with the perchlorate anion. It is an oxidant and strong electrophile, but has fallen out of use with the availability of the closely related salt nitrosonium tetrafluoroborate NO(BF4).

Manganese(II) perchlorate is an inorganic chemical compound with the formula Mn(ClO4)2. It forms a white-colored anhydrous and a rose-colored hexahydrate, both of which are hygroscopic. As a perchlorate, it is a strong oxidizing agent.

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.