I tried to generate a perovskite structure with VESTA, and the following are my settings:
The generated structure seems to be correct. However, when I tried to export it as POSCAR I got the following:
New structure
1.0
5.0000000000 0.0000000000 0.0000000000
0.0000000000 5.0000000000 0.0000000000
0.0000000000 0.0000000000 5.0000000000
Cs Cl Pb
1 9 1
Direct
0.000000000 0.000000000 0.000000000
0.500000000 0.500000000 0.000000000
0.000000000 0.500000000 0.500000000
0.500000000 0.000000000 0.500000000
0.500000000 0.000000000 0.500000000
0.500000000 0.500000000 0.000000000
0.000000000 0.500000000 0.500000000
0.000000000 0.500000000 0.500000000
0.500000000 0.000000000 0.500000000
0.500000000 0.500000000 0.000000000
0.500000000 0.500000000 0.500000000
Seems that each Cl atom is counted thrice. Why did that happen and how should I fix it?