论文标题
用于金属催化的量子蒙特卡洛法：PT上氢产生的案例研究（111）
Quantum Monte Carlo method for metal catalysis: case study of hydrogen production on Pt(111)
论文作者
论文摘要
超过90％的化学生产都使用固体催化剂。因此，相关工作响应了主要的社会需求。这项研究是铂生产的铂的水电转移。封闭式PT（111）表面催化了此过程。 许多化学反应涉及键合。对于固体表面的反应也是如此，在固体表面上，解离步骤通常是限制的，但与气相反应通道相比有助于促进。由于Hartree-Fock和DFT方法对破坏债券的描述很差，因此这项工作采用了量子蒙特卡洛（QMC）方法。 QMC是一种求解Schrödinger方程的随机方法，最近是涉及固体的异质系统的年龄。 目前的工作考虑了Pt上的水和一氧化碳的共吸收（111）。水部分分离，同时其氧原子结合以损失氢原子。这个协调一致的步骤是限制速率的。然后，由此产生的吸附甲酸盐物种分解为易于消除二氧化碳，清洁燃料产品为H $ _2 $。 根据我们使用赌场软件的早期工作，可以使用分子量子蒙特卡洛力常数优化过渡状态几何形状。 我们使用了我们嵌入的活动现场方法。这允许使用高级配置相互作用（CI）波功能，在平面波中扩展并嵌入在金属晶格中，以暴露其闭合的面部。所得的周期函数用于指导量子蒙特卡洛计算。 此处给出了对在17 +/- 0.2 c.f的PT（111）上加入水的水的机理和QMC激活屏障。明显测得的值为17.05 kcal/mol。他们鼓励研究类似或复杂的催化系统。
Over 90 % of all chemical manufacture uses a solid catalyst. Related work thus responds to major societal demand. This study is of water-gas shift on platinum for hydrogen production. The close-packed Pt(111) surface catalyses this process. Many chemical reactions involve bond-dissociation. This is also true for reactions at solid surfaces, in which the dissociation step is often limiting but facilitated in comparison to gas phase reaction channels. Since bond-breaking is poorly described by Hartree-Fock and DFT methods, this work adopts Quantum Monte Carlo (QMC) methodology. QMC is a stochastic approach to solving the Schrödinger equation recently came of age for heterogeneous systems involving solids. The present work considers co-adsorption of water and carbon monoxide on Pt(111). The water is partially dissociated while its oxygen atom binds to CO losing a hydrogen atom. This concerted step is rate-limiting. The resulting adsorbed formate species then decomposes to readily eliminated carbon dioxide and the clean-fuel product is H$_2$. The Transition-State geometry can be optimized using molecular Quantum Monte Carlo force constants, on the basis of our earlier work using the CASINO software. Our embedded active site approach is used. This allows a high-level configuration interaction (CI) wave-function to be used, expanded in plane-waves and embedded in the metal lattice exposing its close-packed face. The resulting periodic function is used to guide the Quantum Monte Carlo calculation. Results are given here on mechanism and QMC activation barrier for water addition to CO pre-adsorbed on Pt(111) of 17 +/- 0.2 c.f. apparent measured value of 17.05 kcal/mol. They are encouraging for investigating similar or complex catalytic systems.
