【摘要】 采用Gaussian98(A.9版)程序密度泛函方法全优化计算了苯与Pt化学吸附作用的位能曲线。计算结果表明:苯与Pt化学吸附作用是苯的最高占有轨道(HOMO)电子迁移到Pt的最低空轨道(LUMO)的结果。苯与Pt的化学吸附位能曲线呈单调下降,吸附作用是一个自发过程。计算得到Pt与单个C原子作用转向与两个C原子作用过程的吸附过渡态和吸附末态,其吸附活化能和吸附作用能分别为-110.0085和-149.6535kJ/mol。吸附末态的HOMO主要由Pt的5d 原子轨道贡献,预示在电催化加氢过程中,Pt的5d 原子轨道将给出电子从而起到催化作用。更多还原

【Abstract】 The potential curve on chemical adsorption of benzene on Pt was worked out by computing full-optimally with density functional B3LYP/LanL2DZ method from Gaussian 98(A.9 version). It was found that the adsorption process was being the HOMO of benzene interacted with the LUMO of Pt and the HOMO electron of benzene transferred to LUMO of Pt. The energy of chemical adsorption monotonously decreased and the adsorption was a spontaneous process. The transition state(TS) and final state(FS) of Pt interaction with single C turning to two C were founded and the adsorption active energy and adsorption energy were -110.0085kJ/mol and -149.6535kJ/mol, respectively. The coefficient of the HOMO in final state was mainly contributed by 5d-orbital of Pt. It was suggested that in hydrogenation of benzene, the 5d-orbital of Pt would given out electron and act as catalyst.更多还原