# Redefine Box Boundaries 

```
-redef_box redef_dim {xlo xhi} {ylo yhi} {zlo zhi}
```
This option allows for the user to redefine box boundaries deleting atoms/elements outside of the new box boundaries. Elements are refined to atmoistics if they intersect the newly defined box boundaries.
The arguments are described below:
`redef_dim` - The dimensions to be redefined. Can be any permutation of `x`, `y`, `z`, `xy`, `yz`, `xz`, `xyz`. The order of the dimensions dictates the order that the new dimensions must be defined