使用VASPKIT寻找正交超胞

本文共有3474个字，关键词：超胞

在研究材料如缺陷性质时，为了使问题简化尽可能选择正交超胞模型。首先简单介绍一下实现原理。超胞基矢(A,B,C)和原胞基矢(a,b,c)满足

\left(\begin{array}{l} \mathbf{A} \\ \mathbf{B} \\ \mathbf{C} \end{array}\right)=\mathbf{M} \cdot\left(\begin{array}{l} \mathbf{a} \\ \mathbf{b} \\ \mathbf{c} \end{array}\right)=\left(\begin{array}{lll} m_1 & m_2 & m_3 \\ n_1 & n_2 & n_3 \\ l_1 & l_2 & l_3 \end{array}\right)\cdot\left(\begin{array}{lll} a_x & a_y & a_z \\ b_x & b_y & b_z \\ c_x & c_y & c_z \end{array}\right)

式中M为变化矩阵，一共9个元素m_i, n_i和l_i，均取整数。只需遍历m_i, n_i和l_i，当A,B,C相互正交则得到正交超胞。接下来我们以Si初级原胞为例演示如何使用VASPKIT寻找正交超胞。

  • 首先准备POSCAR结构
This file is generated by VASPKIT code
 1.000000
    0.0000000000000000    2.7014999999999998    2.7014999999999998
    2.7014999999999998    0.0000000000000000    2.7014999999999998
    2.7014999999999998    2.7014999999999998    0.0000000000000000
   Si
     2
Direct
    0.0000000000000000    0.0000000000000000    0.0000000000000000   Si1
    0.2500000000000000    0.2500000000000000    0.2500000000000000   Si2
  • 接下来运行VASPKIT-800命令
 =================== Structural-Model Options ====================
  800) Build Orthogonal Supercell
  801) Build Vacuum Slab in Specified Direction
  802) Build Random Substitutional Alloy
  803) Build Surface by Specified Miller Indices
  804) Build Heterostructure by Two Specified Slabs
  805) Build Hexagonal Moire Superlattices (Pro-Only)
  806) Build Nanorribon by Specified Chiral Vector (Pro-Only)
  807) Build Nanotube by Specified Chiral Vector (Pro-Only)
  808) Build Nanotube by Specified Orthogonal Slab

 0)   Quit
 9)   Back
 ------------>>
800
 o-------------------------- Warm Tips --------------------------o
    You Can Manually Set MAX_ATOM_NUMBER or/and ANGLE_TOLERANCE
   in the ~/.vaspkit file to Screen the Most Desired Structures.
 o---------------------------------------------------------------o
 -->> (01) Reading Structure from POSCAR File...
 -->> (02) Written ORTHOGONALCELL_0001_0004.vasp File!
 -->> (03) Written ORTHOGONALCELL_0002_0008.vasp File!
 -->> (04) Written ORTHOGONALCELL_0003_0008.vasp File!
 -->> (05) Written ORTHOGONALCELL_0004_0012.vasp File!
 -->> (06) Written ORTHOGONALCELL_0005_0012.vasp File!
 -->> (07) Written ORTHOGONALCELL_0006_0016.vasp File!
 -->> (08) Written ORTHOGONALCELL_0007_0016.vasp File!
 -->> (09) Written ORTHOGONALCELL_0008_0020.vasp File!
 -->> (10) Written ORTHOGONALCELL_0009_0020.vasp File!

经过几十秒至几分钟的等待，VASPKIT一共寻找到原子数从4变化到20共9个正交构型。如果遇到 Error: Structures exceed 1000. Decrease MAX_ATOM_NUMBER in ~/.vaspkit.错误信息，可在~/.vaspkit文件中设置以下三个参数筛选想要的超胞结构：

MAX_ATOM_NUMBER  =  20    超胞包含最多原子数
MIN_ATOM_NUMBER  =  2     超胞包含最少原子数
ANGLE_TOLERANCE  =  0     超胞晶格基矢夹角误差允许在±1°之间变化

随机选取3个构型使用VESTA可视化。

如果您使用VASPKIT，请记得引用哦。

V. Wang, N. Xu, J.-C. Liu, G. Tang, W.-T. Geng, VASPKIT: A User-Friendly Interface Facilitating High-Throughput Computing and Analysis Using VASP Code, Computer Physics Communications 267, 108033, (2021), https://doi.org/10.1016/j.cpc.2021.108033

欢迎关注VASPKIT公众号

「感觉有帮助？一键投喂 牛奶/咖啡/冰阔乐！」

VASPKIT

(๑＞ڡ＜)☆哇~太棒了！

使用微信扫描二维码完成支付

 欢迎关注VASPKIT新公众号 没有了 
添加新评论
暂无评论