A six-dimensional potential energy surface for Ru(0001)(2×2):CO.
A six-dimensional potential energy surface for Ru(0001)(2×2):CO.
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DOI：
10.1063/1.4894083
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发表时间：
2014-09
期刊：
影响因子：
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通讯作者：
G. Füchsel;J. Tremblay;P. Saalfrank
中科院分区：
文献类型：
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作者：
G. Füchsel;J. Tremblay;P. Saalfrank
我们在刚性Ru（0001）表面[Ru（0001）（2×2）：CO]上提出了一氧化碳覆盖率为1/4的新的全局基态势能面（PES）。所有六个吸附自由度被认为是。为了构建PES，我们使用了超过90，000个点，这些点是使用RPBE交换相关泛函和经验货车德瓦尔斯修正用周期性密度泛函理论计算的。这些点用于插值，利用一个自适应的降维过程（CRP）。三种不同的插值方案，提高精度已经实现，从而产生三种口味的CRP PES。CRP PES的产量与DFT参考和实验一致，CO的顶部位置是最稳定的吸附几何形状，最准确的插值与1.69 eV的吸附能。CRP PES表明，平行于表面的扩散受阻的障碍，430毫电子伏，解离促进，但仍然激活。作为第一个“真实的”的应用和进一步测试的新的潜力，六维振动薛定谔方程变分求解到完全耦合，非谐频率和振动波函数的振动，吸附CO分子。这里也发现与实验的良好协议。作为分析，新的PES开辟了一条有效的途径，多维动态。
We present a new global ground state potential energy surface (PES) for carbon monoxide at a coverage of 1/4, on a rigid Ru(0001) surface [Ru(0001)(2×2):CO]. All six adsorbate degrees of freedom are considered. For constructing the PES, we make use of more than 90,000 points calculated with periodic density functional theory using the RPBE exchange-correlation functional and an empirical van der Waals correction. These points are used for interpolation, utilizing a symmetry-adapted corrugation reducing procedure (CRP). Three different interpolation schemes with increasing accuracy have been realized, giving rise to three flavours of the CRP PES. The CRP PES yields in agreement with the DFT reference and experiments, the atop position of CO to be the most stable adsorption geometry, for the most accurate interpolation with an adsorption energy of 1.69 eV. The CRP PES shows that diffusion parallel to the surface is hindered by a barrier of 430 meV, and that dissociation is facilitated but still activated. As a first "real" application and further test of the new potential, the six-dimensional vibrational Schrödinger equation is solved variationally to arrive at fully coupled, anharmonic frequencies and vibrational wavefunctions for the vibrating, adsorbed CO molecule. Good agreement with experiment is found also here. Being analytical, the new PES opens an efficient way towards multidimensional dynamics.