Seminar:

Quantum state resolved dynamics of gas-surface reactions based on high dimensional potential energy surfaces

July 23, 2019

Dr. Bin Jiang from Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical physics, University of Science and Technology of China, Hefei

Photo: Seminar:

Clark Hall Room 214

 

Gas-surface reactions play an important role in many heterogeneous catalysis processes such as methane steam reformation and water-gas shift reactions. An in-depth understanding of these dynamical processes is of great importance and requires a completely dynamical model. However, most of previous theoretical studies have neglected the degrees of freedom of the surface atoms, i.e. within the static surface approximation. Recently, we have developed high-dimensional potential energy surfaces (PESs) including surface atoms for describing the molecule-surface energy exchange, taking advantage of the Behler-Parrinello (BP) type of atomistic neural network (AtNN) method.1 Taking CO2/Ni(100) systems as an example, we show that molecular dynamics simulations on NN PES reproduce well the much more expensive on-the-fly ab-initio molecular dynamics (AIMD) results with much better statistics.2, 3 More importantly, we can obtain a dynamically converged high-dimensional PES with as few as fifty AIMD trajectories, which enable us to predict more demanding state-to-state scattering properties of polyatomic molecules on metal surfaces.4 I will also show some preliminary results for the NO scattering from Au(111) system, for which the importance of an adiabatic PES is emphasized even though the dynamics is apparently non-adiabatic.5 If there is sufficient time, I will briefly talk about our new type of AtNN model, physically inspired from the well-known embedded atom method. Our new implementation is much faster than the BP type of AtNN framework with the same level of accuracy.6

 

 

1 J. Behler, and M. Parrinello, Phys. Rev. Lett. 98, 146401 (2007).

2 Q. Liu, X. Zhou, L. Zhou, Y. Zhang, X. Luo, H. Guo, and B. Jiang, J. Phys. Chem. C 122, 1761 (2018).

3 B. Kolb, X. Luo, X. Zhou, B. Jiang, and H. Guo, J. Phys. Chem. Lett. 8, 666 (2017).

4 Y. Zhang, X. Zhou, and B. Jiang, J. Phys. Chem. Lett. 10, 1185 (2019).

5 R. Yin, Y. Zhang, and B. Jiang (submitted)

6 Y. Zhang and B. Jiang (in prepration)