Aluminium trichloride
The chemical formula of aluminum chloride is AlCl3, which is a compound of chlorine and aluminum. The melting point and boiling point of aluminum chloride are very low, and it will sublimate to covalent compound. Molten aluminum chloride is not easy to conduct electricity, which is different from most salts (such as sodium chloride) containing halogen ions.
AlCl3 adopts "YCl3" structure, which is the most dense stacking structure of Al3 + cube, while Al3 + in AlBr3 accounts for the adjacent tetrahedral space of the most dense stacking frame of Br. When AlCl3 is melted, it forms volatile dimer al2cl6, which contains two three center four electron chlorine bridge bonds. At higher temperature, the dimer of al2cl6 dissociates to form plane triangle AlCl3, which is similar to the structure of boron trifluoride (BF3).
Aluminum chloride is a colorless transparent crystal or a white and light yellow crystalline powder. The vapor of aluminum chloride exists in the form of covalent dimer (al2cl6) either in non-polar solvent or in molten state. Soluble in water and many organic solvents. The aqueous solution is acidic. In the presence of aromatics, aluminum chloride mixed with aluminum can be used to synthesize bis (aromatics) metal complexes.