Nattino Francesco, Galparsoro Oihana, Costanzo Francesca, Díez Muiño Ricardo, Alducin Maite, Kroes Geert-Jan
Leiden Institute of Chemistry, Leiden University, Gorlaeus Laboratories, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, 20018 Donostia-San Sebastián, Spain.
J Chem Phys. 2016 Jun 28;144(24):244708. doi: 10.1063/1.4954773.
Accurately modeling surface temperature and surface motion effects is necessary to study molecule-surface reactions in which the energy dissipation to surface phonons can largely affect the observables of interest. We present here a critical comparison of two methods that allow to model such effects, namely, the ab initio molecular dynamics (AIMD) method and the generalized Langevin oscillator (GLO) model, using the dissociation of N2 on W(110) as a benchmark. AIMD is highly accurate as the surface atoms are explicitly part of the dynamics, but this advantage comes with a large computational cost. The GLO model is much more computationally convenient, but accounts for lattice motion effects in a very approximate way. Results show that, despite its simplicity, the GLO model is able to capture the physics of the system to a large extent, returning dissociation probabilities which are in better agreement with AIMD than static-surface results. Furthermore, the GLO model and the AIMD method predict very similar energy transfer to the lattice degrees of freedom in the non-reactive events, and similar dissociation dynamics.
准确模拟表面温度和表面运动效应对于研究分子-表面反应是必要的，在这类反应中，向表面声子的能量耗散会在很大程度上影响感兴趣的可观测物。我们在此对两种能够模拟此类效应的方法进行了关键比较，即从头算分子动力学（AIMD）方法和广义朗之万振子（GLO）模型，以N2在W(110)上的解离作为基准。AIMD非常精确，因为表面原子明确是动力学的一部分，但这一优势伴随着巨大的计算成本。GLO模型在计算上更为便捷，但以非常近似的方式考虑晶格运动效应。结果表明，尽管GLO模型简单，但它能够在很大程度上捕捉系统的物理过程，给出的解离概率比静态表面结果与AIMD的结果更吻合。此外，GLO模型和AIMD方法在非反应事件中预测到向晶格自由度的能量转移非常相似，解离动力学也相似。
