We discuss a theoretical approach that employs machine learning potential energy surfaces (ML-PESs) in the nonadiabatic dynamics simulation of polyatomic systems by taking 6-aminopyrimidine as a typical example. The Zhu-Nakamura theory is employed in the surface hopping dynamics, which does not require the calculation of the nonadiabatic coupling vectors. The kernel ridge regression is used in the construction of the adiabatic PESs. In the nonadiabatic dynamics simulation, we use ML-PESs for most geometries and switch back to the electronic structure calculations for a few geometries either near the S/S conical intersections or in the out-of-confidence regions. The dynamics results based on ML-PESs are consistent with those based on CASSCF PESs. The ML-PESs are further used to achieve the highly efficient massive dynamics simulations with a large number of trajectories. This work displays the powerful role of ML methods in the nonadiabatic dynamics simulation of polyatomic systems.

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This research details the mundane practices of policy mobility and entrepreneurial endeavour in Jiyuan in relation to the city's changing administrative position, and is one of the first attempts at understanding how entrepreneurial policies are mobilized, mutated and diffused in a small inland Chinese city. We interpret Jiyuan's evolving development strategies and trajectory through two interrelated conceptual lenses—policy mobility and urban entrepreneurialism—bridged by an analysis of the politics of scale. Over the past three decades, governance strategies in Jiyuan have evolved from policy imitation, during the germination of urban entrepreneurialism, to policy mutation and diffusion, under the amplification of entrepreneurialism, as the city has moved up the administrative levels and urban hierarchy. Policy mobility and urban entrepreneurialism in Jiyuan, involving a multi‐scalar process, are being shaped by the interactions between the city, the region, the central state and global capital under the confluence of globalization and marketization. The ‘successful’ story of a small entrepreneurial city tells a new tale that can inform wider contexts by painting a fuller portrait of the evolution of an entrepreneurial city across different scales and time and bringing cities hitherto ‘off the map’ back into the picture of urban entrepreneurialism against the backdrop of globalization.