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[交流] 【求助】ReaxFF 力场参数化问题请教

以下是引自Simulations on the Thermal Decomposition of a Poly(dimethylsiloxane) Polymer Using the ReaxFF Reactive Force Field，J. AM. CHEM. SOC. 2005, 127, 7192-7202的一个片段，是关于ReaxFF力场参数化的说明，不知道具体是怎么执行的，希望有人可以一起探讨下。

The force field was constructed by adding quantum chemical (QC) data for systems relevant to PDMS chemistry to the ReaxFF training set for Si/SiO materials. QC data for nonperiodic systems was obtained from DFT calculations performed using Jaguar (version 5.5) using the B3LYP functional and Pople’s 6-311G**++ basis set.22 The Mulliken charges were obtain using Pople’s 6-31G** basis set. To obtain the equation of state for disiloxane diol (HOMe2Si)2O crystal, DFT calculations were performed with the plane-wave code CASTEP (version 3.8) module in Cerius2. The generalized gradient approximation (GGA) proposed by Perdew, Burke, and Ernzerhof was used for the exchange-correlation energy, and ultrasoft pseudopotentials were used to replace the core electrons. We used the Perdew-Wang implementation of GGA with a kinetic energy cutoff of 380 eV. The Monkhorst-Pack scheme was used to generate the k-space grid with a 0.1 Å-1 spacing

请问以上这些具体是怎么操作的？是不是可以理解成 1）、非周期性体系的QC数据用 DFT的 B3LYP/6-311G**++ 模型进行计算；2）、Mulliken电荷从6-31G**基组的频率计算获得 3）、HOMe2Si的状态方程用Cerius中的CASTEP模块的Plane-wave方法获得；4）、使用PBE-GGA计算关联-交换能，超软赝势代替核电子；5）PW-GGA计算中，动能截断取380eV；6）使用Monkhorst-Pack方案产生k-space格点，空间间隔为0.1埃？

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