Pd6簇与H2分子相互作用的密度泛函理论研究

通过相对论有效核势密度泛函理论计算，优化了Pd6(H)2和Pd6(H)4等簇的平衡几何结构，预测了氢分子在Pd6簇表面上的吸附行为与活化解离性质.计算结果表明，单态的Pd6簇可以活化两个氢分子；第一个H2和第二个H2吸附解离过程速率决定步骤的能垒分别是66.4和24.5kJ/mol、在形成的分子氢配合物Pd6(H2)和Pd（H)2H2中，H2主要作为给电子配体.在最稳定的二氢簇合物Pd6(H)2中，H倾向与3个Pd相互作用，形成面位氢的多核成键吸附方式.

Density Functional Theory Study on the Interaction of Pd6 with Multiple H2

Equilibrium geometries of Pd 6H 2, Pd 6(H) 2 and Pd 6(H) 4 clusters and multiple H 2 adsorption and dissociation on Pd 6 were investigated by density functional theory calculations with the relativistic effective core potential. Present calculations show that barriers of the rate-determining steps for the first H 2 and the second H 2 activation processes are 66 4 and 24 5 kJ/mol, respectively. In the dihydrogen complexes the H 2-ligand behaves as donor in the molecular bonding between H 2 and Pd 6. Chemisorbed hydrogen atoms prefer to bind the Pd 3 facet of Pd 6 in the most stable hydride complex Pd 6(H) 2.