Deraet Xavier, Çilesiz Umut, Aviyente Viktorya, De Proft Frank
Research Group of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050, Brussels, Belgium.
Department of Chemistry, Boğaziçi University, Bebek 34342, Istanbul, Turkey.
J Mol Model. 2024 Oct 22;30(11):380. doi: 10.1007/s00894-024-06173-y.
Single-atom catalytic systems constitute an intriguing research topic due to their inherently different chemical behavior as compared to classic heterogeneous catalysts. In this study, cluster systems representing single late transition metal atoms adsorbed on anatase were constructed starting from previously generated periodic models and subjected to a density functional theory (DFT) benchmark study. The ability of different density functional approximations representing all rungs of the Jacob's Ladder classification to accurately describe bond lengths and adsorption energies was assessed for these clusters with the aim of revealing the functional that allows to retain the structural characteristics of the initial periodic system, while also delivering reliable energetics. In this regard, our results indicate that optimisation of the clusters with the meta-GGA functionals TPSS or RevTPSS provides the lowest mean unsigned error and root-mean-square deviations with respect to the periodic models. Moreover, these functionals and, to a slightly lesser degree, PW91 were also found to provide adsorption energies that are statistically the least deviating from the CCSD(T) reference data. More complex hybrid functionals appear to be performing less well.
Cluster geometries were determined at the Kohn-Sham DFT level using the LANL2DZ basis set for the transition metals and the Pople 6-31G(d) basis set for O and H. The density functional approximations considered were SVWN, PBE, BP86, BLYP, PW91, TPSS, RevTPSS, M06L, M11L, B3LYP, PBE0, M06, M06-2X, MN15, ωB97X-D, CAM-B3LYP, M11, and MN12-SX. Reference adsorption energies of the metals on the support cluster were obtained at the CCSD(T)/LANL2TZ (transition metals)/6-311 + + G(d,p)//RevTPSS/LANLD2DZ (transition metals)/6-31G*. Besides the above-mentioned functionals, energy calculations using the double-hybrid functionals, DSDPBEP86, PBE0-DH, and B2PLYP, were also performed. All adsorption energy calculations were carried out on the RevTPSS geometries.
单原子催化体系是一个引人入胜的研究课题，因为与传统的多相催化剂相比，它们具有本质上不同的化学行为。在本研究中，从先前生成的周期性模型出发构建了代表吸附在锐钛矿上的单个晚期过渡金属原子的簇体系，并对其进行了密度泛函理论（DFT）基准研究。针对这些簇，评估了代表雅各布阶梯分类所有梯级的不同密度泛函近似准确描述键长和吸附能的能力，目的是揭示既能保留初始周期性体系的结构特征，又能提供可靠能量学的泛函。在这方面，我们的结果表明，使用元广义梯度近似（meta-GGA）泛函TPSS或RevTPSS对簇进行优化，相对于周期性模型，平均无符号误差和均方根偏差最低。此外，还发现这些泛函以及在稍小程度上的PW91所提供的吸附能在统计上与耦合簇双激发组态相互作用方法（CCSD(T)）参考数据的偏差最小。更复杂的杂化泛函表现似乎较差。
使用用于过渡金属的LANL2DZ基组和用于O和H的Pople 6-31G(d)基组，在Kohn-Sham DFT水平上确定簇的几何结构。所考虑的密度泛函近似有SVWN、PBE、BP86、BLYP、PW91、TPSS、RevTPSS、M06L、M11L、B3LYP、PBE0、M06、M06-2X、MN15、ωB97X-D、CAM-B3LYP、M11和MN12-SX。金属在支撑簇上的参考吸附能在CCSD(T)/LANL2TZ（过渡金属）/6-311++G(d,p)//RevTPSS/LANLD2DZ（过渡金属）/6-31G*水平上获得。除上述泛函外，还使用双杂化泛函DSDPBEP86、PBE0-DH和B2PLYP进行了能量计算。所有吸附能计算均在RevTPSS几何结构上进行。
