Solvation Free Energies and Adsorption Energies at the Metal/Water Interface from Hybrid Quantum-Mechanical/Molecular Mechanics Simulations
Solvation Free Energies and Adsorption Energies at the Metal/Water Interface from Hybrid Quantum-Mechanical/Molecular Mechanics Simulations
复制标题
混合量子力学/分子力学模拟中金属/水界面处的溶剂化自由能和吸附能
DOI：
10.1021/acs.jctc.0c00632.s001
复制
发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Steinmann
中科院分区：
文献类型：
--
作者：
Paul Clabaut;Benjamin Schweitzer;A. Götz;C. Michel;Stéphan;Steinmann
金属/水界面的吸附建模是加深对从多相催化到腐蚀等各个领域的理解的基石。我们提出并验证了一种混合方案，该方案将 DFT 水平下气相中获得的吸附自由能与使用基于分子力学的炼金转化（表示为 MMsolv）评估的从体相到界面的溶剂化变化相结合。使用铂/水相互作用的 GAL17 力场，我们检索了界面处水溶剂的定性正确的相互作用能。这种相互作用具有接近化学吸附的特性，因此对于炼金转化和固定点电荷静电学来说都具有挑战性。我们的方案经过一个以 Pt(111)/H 2 O 相互作用的良好物理吸附势为特征的状态，以收敛自由能差。该工作流程在免费提供的 SolvHybrid 包中实现。我们首先评估水分子在 Pt/水界面的吸附，结果证明这是一项严格的测试。通过引入校正项来减弱近化学吸附的水分子与下面的 Pt 原子之间的静电相互作用，我们的 QM-MM 混合方案的固有误差被限制在 6 kcal·mol − 1 以内。接下来，我们表明 Pt 的 MMsolv 溶剂化自由能 (-0.46 J·m − 2 ) 与实验估计 (-0.32 J·m − 2 ) 非常吻合。此外，我们还表明，室温下的熵贡献与自由能的大小大致相同，但符号相反。最后，我们计算了 Pt(111)/水界面上苯和苯酚的吸附能，这是可获得实验数据的罕见系统之一。与实验定性一致，但与标准隐式溶剂模型形成鲜明对比，与固/气界面相比，这些芳香族分子在固/液界面处的吸附大大减少（即，对于我们的 QM/MM 混合方案和实验，放热分别减少 ∼ 30 和 40 kcal·mol − 1，但对于隐式溶剂为 ∼ 0）。这种减少主要是由于有机吸附物和溶剂之间对金属表面吸附的竞争。与芳香族分子吸附能的实验估计的半定量一致性验证了我们的混合 QM-MM 方案的合理性。
Modeling adsorption at the metal/water interfaces is a corner-stone towards an improved understanding in a variety of fields from heterogeneous catalysis to corrosion. We propose and validate a hybrid scheme that combines the adsorption free energies obtained in gas phase at the DFT level with the variation in solvation from the bulk phase to the interface evaluated using a molecular mechanics based alchemical transformation, denoted MMsolv. Using the GAL17 force field for the platinum/water interaction, we retrieve a qualitatively correct interaction energy of the water solvent at the interface. This interaction is of near chemisorption character and thus challenging, both for the alchemical transformation, but also for the fixed point-charge electrostatics. Our scheme passes through a state characterized by a well-behaved physisorption potential for the Pt(111)/H 2 O interaction to converge the free energy difference. The workflow is implemented in the freely available SolvHybrid package. We first assess the adsorption of a water molecule at the Pt/water interface, which turns out to be a stringent test. The intrinsic error of our QM-MM hybrid scheme is limited to 6 kcal · mol − 1 through the introduction of a correction term to attenuate the electrostatic interaction between near-chemisorbed water molecules and the underlying Pt atoms. Next, we show that the MMsolv solvation free energy of Pt (-0.46 J · m − 2 ) is in good agreement with the experimental estimate (-0.32 J · m − 2 ). Furthermore, we show that the entropy contribution at room temperature is roughly of equal magnitude as the free energy, but with opposite sign. Finally, we compute the adsorption energy of benzene and phenol at the Pt(111)/water interface, one of the rare systems for which experimental data are available. In qualitative agreement with experiment, but in stark contrast with a standard implicit solvent model, the adsorption of these aromatic molecules is strongly reduced (i.e., less exothermic by ∼ 30 and 40 kcal · mol − 1 for our QM/MM hybrid scheme and experiment, respectively, but ∼ 0 with the implicit solvent) at the solid/liquid compared to the solid/gas interface. This reduction is mainly due to the competition between the organic adsorbate and the solvent for adsorption on the metallic surface. The semi-quantitative agreement with experimental estimates for the adsorption energy of aromatic molecules thus validates the soundness of our hybrid QM-MM scheme.
登录
查看更多内容
影响因子：
62.1
作者：
Liu L;Corma A
通讯作者：
Corma A
影响因子：
4.6
作者：
Gim, Suji;Cho, Kang Jin;Kim, Hyungjun
通讯作者：
Kim, Hyungjun
高强度激光与簇介质相互作用产生的激光驱动辐射爆炸波
DOI：
--
发表时间：
2016
期刊：
影响因子：
--
作者：
加藤郁也;脇坂優美;南本大穂;村越 敬;福田祐仁
通讯作者：
福田祐仁
SWNT/金属界面的表面电势分析
DOI：
--
发表时间：
2007
期刊：
J. Appl. Phys. 101
影响因子：
--
作者：
M.;Shiraishi;K.;Takebe;K.;Saito;N.;Toda;H.;Kataura;M.Shiraishi et al.
通讯作者：
M.Shiraishi et al.