The application of the molecular dynamics simulation based one the molecular orbital calculation to the vitreous state

基于分子轨道计算的分子动力学模拟在玻璃态中的应用

• 批准号: 13650734
• 负责人: INOUE Hiroyuki
• 金额: $ 0.9万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650734/
• 关键词: Molecular Dynamics; Glass structure; Molecular Orbital; Three-body potential; SiO_2 Glass; Vibrational spectrum; Cluster calculation; Electronic state; ガラス構造モデル; 電荷移動; 原子間ポテンシャル; SiO2ガラス; 原子間振動スペクトル; 電子状態の考慮

The molecular dynamics (MD) simulation with electronic state, which was calculated by use of molecular orbital method, was produced and the vitreous state was simulation by this method.. The potential energies of the clusters were calculated using GAMESS, which is one of the programs for ab initio molecular orbital method. By decomposing the potential energies in the potential function of the atomic distance and the bond angle, the parameter of the potential function was estimated. We applied this method to SiO_2, B_2O_3 and P_2O_5 systems.The parameters of the function of the atomic distance and bond angle could be obtained. (1)The radial distribution curves calculated from the structural models obtained from the molecular dynamics simulation using the obtained potentials and they were compared with the observed ones. (2)The vibrational spectra were calculated from the trace of the coordinates of the simulation. We also calculated radial distribution curves and vibrational spectra from the structural models based on TTAM and BKS potentials. The agreement of the radial distribution curves and vibrational modes and wavenumber, could be obtained from the structural models of our simulations. However, it is difficult to find that the potential parameters. The radial distribution curves and vibrationl frequencies calculated using the parameters be agreed with the observed ones simultaneously. The two-body potentials for B2O3 and P2O5 systems were evaluated. It was confirmed that the vitreous state using the potential parameters and that the structure models, which correspond to the crystal structure could be obtained.

利用分子轨道法计算电子态的分子动力学（MD）模拟，并用该方法模拟玻璃态。使用GAMESS计算团簇的势能，GAMESS是一种计算团簇的势能。从头算分子轨道法程序。通过将势能分解为原子距离和键角的势函数，估计了势函数的参数。我们将该方法应用到SiO_2、B_2O_3和P_2O_5体系中，得到了原子距离和键角函数的参数。 (1)利用获得的势，根据分子动力学模拟获得的结构模型计算出径向分布曲线，并将其与观测值进行比较。 (2)根据模拟坐标的轨迹计算振动谱。我们还根据 TTAM 和 BKS 势的结构模型计算了径向分布曲线和振动谱。从我们模拟的结构模型中可以获得径向分布曲线和振动模式和波数的一致性。然而，很难找到潜在的参数。利用这些参数计算出的径向分布曲线和振动频率与观测值同时吻合。评估了 B2O3 和 P2O5 系统的二体势。证实了使用电势参数的玻璃态以及可以获得与晶体结构相对应的结构模型。