aC_JCP_2023

The amorphous carbon dataset was generated using ab initio calculations with VASP software. We utilized the LDA exchange-correlation functional and the PAW potential for carbon. Melt-quench simulations were performed to create amorphous and liquid-state structures. A simple cubic lattice of 216 carbon atoms was chosen as the initial state. Simulations were conducted at densities of 1.5, 1.7, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, and 3.5 g/cm3 to produce a variety of structures. The NVT ensemble was employed for all melt-quench simulations, and the density was adjusted by modifying the size of the simulation cell. A time step of 1 fs was used for the simulations. For all densities, only the Γ points were sampled in the k-space. To increase structural diversity, six independent simulations were performed.In the melt-quench simulations, the temperature was raised from 300 K to 9000 K over 2 ps to melt carbon. Equilibrium molecular dynamics (MD) was conducted at 9000 K for 3 ps to create a liquid state, followed by a decrease in temperature to 5000 K over 2 ps, with the system equilibrating at that temperature for 2 ps. Finally, the temperature was lowered from 5000 K to 300 K over 2 ps to generate an amorphous structure.During the melt-quench simulation, 30 snapshots were taken from the equilibrium MD trajectory at 9000 K, 100 from the cooling process between 9000 and 5000 K, 25 from the equilibrium MD trajectory at 5000 K, and 100 from the cooling process between 5000 and 300 K. This yielded a total of 16,830 data points.Data for diamond structures containing 216 atoms at densities of 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, and 3.5 g/cm3 were also prepared. Further data on the diamond structure were obtained from 80 snapshots taken from the 2 ps equilibrium MD trajectory at 300 K, resulting in 560 data points.To validate predictions for larger structures, we generated data for 512-atom systems using the same procedure as for the 216-atom systems. A single simulation was conducted for each density. The number of data points was 2,805 for amorphous and liquid states本非晶碳数据集采用VASP软件开展从头算（ab initio）计算生成。我们选用局域密度近似（LDA）交换关联泛函与投影缀加波（PAW）碳势。为构建非晶态与液态碳结构，我们开展了熔淬模拟。初始态选取包含216个碳原子的简单立方晶格。模拟在1.5、1.7、2.0、2.2、2.4、2.6、2.8、3.0、3.2、3.4及3.5 g/cm³的密度下进行，以生成多样化的结构。所有熔淬模拟均采用正则系综（NVT ensemble），通过调整模拟盒子的尺寸来调控体系密度。模拟的时间步长设为1飞秒（fs）。针对所有密度点，倒易空间仅采样Γ点。为提升结构多样性，我们共开展了6组独立模拟。 在熔淬模拟中，体系温度于2皮秒（ps）内从300 K升至9000 K以实现碳的熔融；随后在9000 K下进行3皮秒的平衡分子动力学（MD）模拟以获得液态结构；接着将温度在2皮秒内降至5000 K，并在该温度下平衡2皮秒；最终将温度在2皮秒内从5000 K降至300 K，从而得到非晶态结构。 熔淬模拟过程中，我们从9000 K下的平衡MD轨迹中提取30帧快照，从9000 K至5000 K的降温过程中提取100帧，从5000 K下的平衡MD轨迹中提取25帧，从5000 K至300 K的降温过程中提取100帧，总计得到16830个数据点。 我们还制备了密度分别为2.4、2.6、2.8、3.0、3.2、3.4及3.5 g/cm³、包含216个原子的金刚石结构数据。此外，从300 K下2皮秒的平衡MD轨迹中提取80帧快照，进一步得到560个金刚石结构数据点。 为验证针对更大尺寸结构的预测能力，我们参照216原子体系的流程，生成了包含512个原子的体系数据。针对每个密度点开展一次模拟，非晶态与液态态的数据点总数为2805。

搜集汇总

背景与挑战

背景概述

该数据集是一个无定形碳计算数据集，通过VASP软件进行ab initio计算生成，采用熔融淬火模拟在多个密度（1.5至3.5 g/cm³）下创建无定形和液态结构，并包含金刚石结构数据。数据集包含总计约2万个数据点，涵盖216和512原子系统，旨在提供多样化的结构状态以支持材料科学中的预测验证和模型训练。