Structural Evolution of C60 Molecular Crystal Predicted by Neural Network Potential
Structural Evolution of C60 Molecular Crystal Predicted by Neural Network Potential
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DOI：
10.1002/adfm.202203894
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发表时间：
2022-08
影响因子：
19
通讯作者：
Kun Ni;Fei Pan;Yanwu Zhu
中科院分区：
文献类型：
--
作者：
Kun Ni;Fei Pan;Yanwu Zhu
富勒烯及其衍生物的制备在过去的几十年里引起了人们的广泛关注。理解富勒烯开始的结构演化对于指导实验探索是至关重要的，但尚未受到足够的重视。用从头算分子动力学或全局结构搜索算法结合密度泛函理论计算可以得到势能面（PES），但成本高、效率低。本文利用神经网络势函数和随机表面行走全局结构搜索方法，从C60分子晶体出发，加速能量计算，实现高效PES映射。零压下结构演化遵循分子晶体→聚合物→开笼有序结构→三维弯曲碳和石墨的顺序。在高压下，例如，50 GPa时，其演化遵循富勒烯→ sp2和sp3杂化碳→ sp3非晶碳和晶体金刚石的路径。在演化途径中所获得的结构的电子性质计算示出了取决于所生成的结构的序参数的带隙，这表明从C60开始，可以在实验中潜在地制备更多的新型碳。
The preparation of fullerene and a wide range of derivatives has attracted much attention in past decades. Understanding the structural evolution starting from fullerene is critical to guide the experimental exploration but has been paid less attention yet. Using ab initio molecular dynamics or global structural search algorithm accompanied with density functional theory calculations can give a glance of the potential energy surface (PES), but suffers high cost and low efficiency. Herein, by using neural network potentials and stochastic surface walking global structural search method, an accelerated energy calculation, and the higher efficient PES mapping starting from C60 molecular crystal are reported. The structural evolution is found to follow an order of molecular crystal → polymers → opened caged ordered structures → 3D) curved carbon and graphite under zero pressure. Under high pressures, e.g., 50 GPa, the evolution follows a pathway of fullerene → sp2 and sp3 hybrid carbon → sp3 amorphous carbon and crystal diamond. The electronic property calculation of the obtained structures in the evolution pathway shows a band gap depending on the order parameter of the generated structures, suggesting that more novel carbons can be potentially prepared in experiments, starting from C60.