Reactions in the Al-H-Cl System Studied by ab Initio Molecular Orbital and Density Functional Methods

High-level ab initio quantum chemical calculations have been used to investigate possible reactions in the Al-H-Cl system. Transition states or barrierless reaction paths have been identified for essentially all feasible reactions in this system involving a single aluminum atom. Structures, energies, and vibrational frequencies for reactants, products, and transition states in this system are presented. These results provide a basis for the estimation of reaction rate parameters for this system using transition state theory and related unimolecular reaction rate theories and thereby construct a reaction mechanism useful for detailed chemical kinetic modeling of aluminum combustion in HCl and chemical vapor deposition using AlCl3 in H2. In the few cases where previous experimental or theoretical results have been published, the present work is consistent with previous work.