A theoretical approach to the photochemical activation of matrix isolated aluminum atoms and their reaction with methane

作者：Pacheco Blas M A^*; Novaro O A; Pacheco Sanchez J H

来源：Journal of Chemical Physics, 2010, 133(17): 174307.

DOI：10.1063/1.3499813

The photochemical activation of Al atoms in cryogenic matrices to induce their reaction with methane has been experimentally studied before. Here, a theoretical study of the nonadiabatic transition probabilities for the ground ((2)P: 3s(2)3p(1)) and the lowest excited states ((2)S: 3s(2)4s(1) and (2)D: 3s(2)3d(1)) of an aluminum atom interacting with a methane molecule (CH(4)) was carried out through ab initio Hartree-Fock self-consistent field calculations. This was followed by a multiconfigurational study of the correlation energy obtained by extensive variational and perturbational configuration interaction analyses using the CIPSI program. The (2)D state is readily inserted into a C-H bond, this being a prelude to a sequence of avoided crossings with the initially repulsive (to CH(4)) lower lying states (2)P and (2)S. We then use a direct extension of the Landau-Zener theory to obtain transition probabilities at each avoided crossing, allowing the formation of an HAlCH(3) intermediate that eventually leads to the final pair of products H + AlCH(3) and HAl + CH(3).

• 出版日期2010-11-7