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/ These are the examples of ABACUS program.
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ABACUS supports adding a distribution of compensating charge to maintain the supercell's neutrality due to the periodic boundary condition. The compensating charge implemented in ABACUS follows the [methodology](http://dx.doi.org/10.1103/PhysRevB.89.245406) developed by Brumme, Calandra, and Mauri in 2014.

The ditrubution of compensating charge can be added with the following 
parameters in INPUT file, 

```
INPUT_PARAMETERS
gate_flag           1
zgate               0.7
block_down          0.65
block_up            0.75
block_height        0.01
block               1
nelec               487
```

Detailed explaination of these keywords can be found [here](https://github.com/deepmodeling/abacus-develop/blob/develop/docs/input-main.md#gate-field-compensating-charge). An additional electron is included via `nelec` so as to trigger on the positive compensating charge. The energy contribution from the compensating charge is given as `E_gatefield` in the output file. See `running_scf.ref` for the output of this example. Note that both `pw` and `lcao` (specified via `basis type`) are supported for this functionality.