Davis Jack B A, Baletto Francesca, Johnston Roy L
School of Chemistry, University of Birmingham , Birmingham, West Midlands B15 2TT, United Kingdom.
Department of Physics, Kings College London , London WC2R 2LS, United Kingdom.
J Phys Chem A. 2015 Sep 17;119(37):9703-9. doi: 10.1021/acs.jpca.5b05710. Epub 2015 Sep 8.
The effect of dispersion corrections at a range of theory levels on the chemisorption properties of metallic nanoparticles is presented. The site preference for CO on Pt, Au, Pd, and Ir nanoparticles is determined for two geometries, the 38-atom truncated octahedron and the 55-atom icosahedron using density functional theory (DFT). The effects of Grimme's DFT-D2 and DFT-D3 corrections and the optPBE vdW-DF on the site preference of CO is then compared to the "standard" DFT results. Functional behavior is shown to depend not only on the metal but also on the geometry of the nanoparticle with significant effects seen for Pt and Au. There are both qualitative and quantitative differences between the functionals, with significant energetic differences in the chemical ordering of inequivalent sites and adsorption energies varying by up to 1.6 eV.
本文介绍了一系列理论水平下色散校正对金属纳米颗粒化学吸附性质的影响。使用密度泛函理论（DFT），针对两种几何结构（38原子截角八面体和55原子二十面体）确定了CO在Pt、Au、Pd和Ir纳米颗粒上的吸附位点偏好。然后将Grimme的DFT-D2和DFT-D3校正以及optPBE vdW-DF对CO吸附位点偏好的影响与“标准”DFT结果进行比较。结果表明，泛函行为不仅取决于金属，还取决于纳米颗粒的几何结构，在Pt和Au上观察到显著影响。不同泛函之间存在定性和定量差异，不等价位点的化学排序存在显著能量差异，吸附能变化高达1.6 eV。
