# electrons

Describes the electrons. For the moment, only the number of alpha and beta electrons are provided by this module.

## Assumptions

- `elec_num` >= 0
- `elec_alpha_num` >= 0
- `elec_beta_num` >= 0
- `elec_alpha_num` >= `elec_beta_num`

### EZFIO parameters

`elec_alpha_num```

  Numbers of electrons alpha (“up”)

`elec_beta_num```

  Numbers of electrons beta (“down”)

`elec_num```

  Numbers total of electrons (alpha + beta)

  Default: = electrons.elec_alpha_num + electrons.elec_beta_num

### Providers

`elec_num`

  File : `electrons/electrons.irp.f`

      integer :: elec_num
      integer, allocatable    :: elec_num_tab (2)

  Numbers of alpha (“up”) , beta (“down”) and total electrons

  Needs:

  `elec_alpha_num` | `elec_beta_num` | `ezfio_filename`

  Needed by:

  `diagonal_h_matrix_on_psi_det` `psi_det_hii` | `psi_selectors_diag_h_mat` | `pt2_f`

`elec_num_tab`

  File : `electrons/electrons.irp.f`

      integer :: elec_num
      integer, allocatable    :: elec_num_tab (2)

  Numbers of alpha (“up”) , beta (“down”) and total electrons

  Needs:

  `elec_alpha_num` | `elec_beta_num` | `ezfio_filename`

  Needed by:

  `diagonal_h_matrix_on_psi_det` `psi_det_hii` | `psi_selectors_diag_h_mat` | `pt2_f`