问一下楼主，你从哪里知道CHGCAR的单位就是e/Bohr^3呢？
我最近看了一些相关资料知道，CHGCAR的单位应该是e, 要获得真正的电荷密度需要再除以晶包体积，如果你晶胞体积采用的是Bohr为单位，那么得到的电荷密度就是以e/Bohr^3为单位i，反之，如果晶胞采用A为单位，那么电荷密度就应该是以e/A^3为单位。

VASP说明书上有这样一句话：
“CHGCAR file
This file contains the lattice vectors, atomic coordinates, the total charge density multiplied by the volume  on the fine FFT-grid (NG(X,Y,Z)F)”

“ Please do not forget to divide by the volume before visualizing the file!”，

看VESTA手册上面说的

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When these files are read in to visualize isosurfaces and sections, data values are divided by V in the unit of bohr3. The unit of charge densities input by VESTA is, therefore, bohr−3.