Bramley Gabriel, Nguyen Manh-Thuong, Glezakou Vassiliki-Alexandra, Rousseau Roger, Skylaris Chris-Kriton
School of Chemistry, University of Southampton, Southampton SO17 1BJ, U.K.
Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States.
J Chem Theory Comput. 2020 Apr 14;16(4):2703-2715. doi: 10.1021/acs.jctc.0c00034. Epub 2020 Mar 27.
Implicit solvent models are a computationally efficient method of representing solid/liquid interfaces prevalent in electrocatalysis, energy storage, and materials science. However, electronic structure changes induced at the metallic surface by the dielectric continuum are not fully understood. To address this, we perform DFT calculations for the Pt(111)/water interface, in order to compare Poisson-Boltzmann continuum solvation methods with molecular dynamics (AIMD) simulations of explicit solvent. We show that the implicit solvent cavity can be parametrized in terms of the electric dipole moment change at the equilibrated explicit Pt/water interface to obtain the potential of zero charge (PZC). We also compare the accuracy of aqueous enthalpies of adsorption of phenol on Pt(111) using geometry and charge density based dielectric cavitation methods. The ability to parametrize the cavity according to individual atoms, as afforded in the geometry based approach, is key to obtaining accurate enthalpy changes of adsorption under aqueous conditions. We also show that the electronic structure changes induced by explicit solvent and our proposed implicit solvent parametrization scheme yield comparable density difference profiles and d-band projected density of states. We therefore demonstrate the capability of implicit solvent approaches to capture both the energetics of adsorption processes and the main electronic effects of aqueous solvent on the metallic surface. This work therefore provides a scheme for computationally efficient simulations of interfacial processes for applications in areas such as heterogeneous catalysis and electrochemistry.
隐式溶剂模型是一种计算效率高的方法，用于表示电催化、能量存储和材料科学中普遍存在的固/液界面。然而，由介电连续介质在金属表面引起的电子结构变化尚未完全理解。为了解决这个问题，我们对Pt(111)/水界面进行了密度泛函理论（DFT）计算，以便将泊松-玻尔兹曼连续介质溶剂化方法与显式溶剂的分子动力学（AIMD）模拟进行比较。我们表明，隐式溶剂腔可以根据平衡的显式Pt/水界面处的电偶极矩变化进行参数化，以获得零电荷电势（PZC）。我们还使用基于几何和电荷密度的介电空穴方法比较了苯酚在Pt(111)上的水相吸附焓的准确性。基于几何的方法中根据单个原子对空穴进行参数化的能力，是在水相条件下获得准确吸附焓变的关键。我们还表明，显式溶剂和我们提出的隐式溶剂参数化方案引起的电子结构变化产生了可比的密度差分布和d带投影态密度。因此，我们证明了隐式溶剂方法能够捕捉吸附过程的能量学以及水相溶剂对金属表面的主要电子效应。因此，这项工作提供了一种计算效率高的方案，用于模拟界面过程，以应用于多相催化和电化学等领域。
