Calculation of interaction of AlCl, AlCl2 and AlCl3 on Al4C3 (001) Al4CO4 (001) and Al2CO (001) planes

To make sure the intermediate products of the carbothermic reduction of Al2O3 process, such as Al4CO4, Al2CO and Al4C3, and the interaction of AlCl, AlCl2, AlCl3 with Al4CO4, Al2CO and Al4C3, respectively, thermodynamic analyses were used to study the chloride reaction production of them under the vacuum situation. The stable structures and electronic properties of AlCl, AlCl2 and AlCl3 adsorbed on Al4CO4, Al2CO and Al4C3 were calculated by first-principles calculations by the CASTEP module in the Materials Studio program. The results show that the AlCl3 and AlCl2 molecules have decomposed on the plane of Al4C3 (001), while there are no obvious decomposition of AlCl3 and AlCl2 on Al4CO4 (001) and Al2CO (001) planes. The adsorption of AlCl on the Al4CO4 (001) and Al2CO (001) planes is stronger than that on the Al4C3(001) plane. The interaction strength of AlCl3, as well as AlCl2, with Al4CO4, Al2CO and Al4C3 is in the sequence of Al4CO4<Al2CO<Al4C3, while the interaction strength of AlCl with Al4CO4, Al2CO and Al4C3 is in the sequence of Al4CO4>Al2CO>Al4C3.