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标题: 如何给表面金属加/减电荷 [打印本页]

作者
Author: bingomini 时间: 2023-7-28 23:42
标题: 如何给表面金属加/减电荷
本帖最后由 bingomini 于 2023-7-28 23:45 编辑

各位老师：
我在文献中看到这样的计算方法，特别是黄色字部分，我不清楚cp2k是怎么实现给金属表面加减电荷的。还是说这个计算方法是不是没讲清楚？谢谢大家！

Ab initio molecular dynamics (AIMD) simulations: AIMD were performed by using the CP2K package. PBE functional with Grimme D3 correction was used to describe the system.
Kohn-Sham DFT has been used as the electronic structure method in the framework of the Gaussian and plane waves method [5, 6]. The Goedecker-Teter-Hutter (GTH) pseudopotentials,
DZVP-MOLOPT-GTH basis sets were utilized to describe the molecules. A plane-wave energy cut-off of 500 Ry has been employed. The NVT ensemble has been performed at 300 K
using Second-Generation Car-Parrinello molecular dynamics method with the time step of 0.5 fs. The simulation has been pre-euiquilibrate for 3ps, and 7 ps trajectory have been used for
analysis. The simulation is carried out on the Zn (002) surface in a three-dimensional periodic boundary box of 15.78 ×13.66 × 28.02 Å3. The Langeivin friction coefficient is set to 0.001
and intrinsic friction coefficient for Zinc surface is 1E-4, while water and molecule are 4E-4. The different charged states of the electrode were simulated by adjusting the charge densities
of the systems. Two electrons were inserted/remove to the system resulting in the surface charge densities of ±7.36 µC cm-2. Besides, the zero charge of the electrode are also conducted by
fixing the surface charge to neutral. The charge densities of the above three simulated systems are denoted as +2e0, 0 and -2e0, respectively. All systems start from the same initial configuration.

作者
Author: yxdd98 时间: 2023-7-29 08:31
请问这个给表面加电荷的方法是出自哪篇文献呢？

作者
Author: bingomini 时间: 2023-7-29 09:12

yxdd98 发表于 2023-7-29 08:31
请问这个给表面加电荷的方法是出自哪篇文献呢？

老师，这是我们最近审稿的一篇论文，我觉得他的计算方法是不是写的有些含糊了？从他的计算方法是不是看不出来是怎么做的呢？

作者
Author: pal 时间: 2023-7-29 09:19
应该就是给整个体系设置了电荷，可以算一下表面电荷密度是不是就是电荷除以表面积，感觉算一下稳定后的表面实际电荷更合理

作者
Author: yxdd98 时间: 2023-7-29 09:43

bingomini 发表于 2023-7-29 09:12
老师，这是我们最近审稿的一篇论文，我觉得他的计算方法是不是写的有些含糊了？从他的计算方法是不是看不 ...

如果是像4楼说得直接设置了整体电荷的话，那给出随着盒子尺寸变化收敛的结果会更好些，因为这种带电盒子的确容易出现这种收敛问题；此外，还有像在slab附近放钠原子、加抗衡离子等，但就作者给出的计算细节貌似也没体现这些。

作者
Author: sobereva 时间: 2023-7-29 12:41
这slab也太薄了

作者
Author: bingomini 时间: 2023-8-9 15:09

sobereva 发表于 2023-7-29 12:41
这slab也太薄了

这个文章的计算方法给的也太模糊了，最后发在了AM上

作者
Author: bingomini 时间: 2023-8-9 15:11

yxdd98 发表于 2023-7-29 09:43
如果是像4楼说得直接设置了整体电荷的话，那给出随着盒子尺寸变化收敛的结果会更好些，因为这种带电盒子 ...

我猜也是在表面附近加了Na或者抗衡原子，我们不同意发表，写了意见问具体是怎么做的，编辑直接给他们接收了= =

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