Calculation of two-dimensional potential energy surfaces of CO on a rutile(110) surface: ground and excited states
Calculation of two-dimensional potential energy surfaces of CO on a rutile(110) surface: ground and excited states
复制标题
金红石 (110) 表面上 CO 二维势能面的计算：基态和激发态
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
T. Klüner
中科院分区：
文献类型：
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作者：
M. Mehring;T. Klüner
作为最重要的催化活性金属氧化物表面之一，本研究的目的是描述激光诱导CO从TiO2（110）表面的光解吸。作为第一步，本文给出了CO分子在金红石型TiO2（110）表面的二维势能面。聚焦于该吸附-基质体系中发生的解吸机理，通过对解吸坐标Z和极角θ的量子化学和量子动力学计算，首次深入了解了CO-TiO2（110）体系中与激光诱导光解吸相关的机制过程。对于电子基态X1A1，当极性角θ = 0°时，吸附量最小，对应于CO与碳原子的线性配位，直至底物表面。这与电子激发态A3B2形成对比，在A3B2中，当极性角θ = 180°时，吸附最小值被发现，这描述了与金红石型TiO2（110）表面上CO分子的氧原子的线性配位。此外，本文还展示了模拟激光诱导光解吸的示例性量子动力学计算，作为详细了解解吸过程的第一步。因此，需要对衬底表面CO分子的2个以上自由度进行高维计算，才能完整地描述这种复杂的吸附-衬底体系。
Being one of the most important catalytically active metal oxide surfaces, the aim of this study was the description of the laser-induced photodesorption of the CO adsorbate from a TiO2(110) surface. As a first step, this paper presents two-dimensional potential energy surfaces of a CO molecule on a rutile TiO2(110) surface. Focussing on the desorption mechanism taking place in this adsorbate–substrate system, the quantum chemical and quantum dynamical calculations regarding the desorption coordinate Z and the polar angle θ allowed a first insight into the mechanistic processes in the CO–TiO2(110) system which are relevant for laser-induced photodesorption. For the electronic ground state X1A1 the adsorption minimum was found for the polar angle θ = 0°, which corresponds to a linear coordination of the CO adsorbate with the carbon atom down to the substrate surface. This is in contrast to the electronically excited state A3B2, where the adsorption minimum was found for the polar angle θ = 180°, which describes a linear coordination with the oxygen atom of the CO molecule on top of the rutile TiO2(110) surface. Moreover, this paper shows exemplary quantum dynamical calculations which simulate the laser-induced photodesorption as a first step to understand the desorption process in detail. Hence, higher dimensional calculations regarding more than 2 degrees of freedom of the CO molecule on the substrate surface are needed to get a complete description of this complex adsorbate–substrate system.