65 lines
1.8 KiB
ReStructuredText
65 lines
1.8 KiB
ReStructuredText
============
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perturbation
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============
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All subroutines in ``*.irp.f`` starting with `pt2_` in the current directory are
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perturbation computed using the routine `i_H_psi`. Other cases are not allowed.
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The arguments of the `pt2_` are always:
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.. code-block:: fortran
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subroutine pt2_...( &
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psi_ref, &
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psi_ref_coefs, &
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E_refs, &
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det_pert, &
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c_pert, &
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e_2_pert, &
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H_pert_diag, &
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Nint, &
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Ndet, &
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N_st )
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integer , intent(in) :: Nint,Ndet,N_st
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integer(bit_kind), intent(in) :: psi_ref(Nint,2,Ndet)
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double precision , intent(in) :: psi_ref_coefs(Ndet,N_st)
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double precision , intent(in) :: E_refs(N_st)
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integer(bit_kind), intent(in) :: det_pert(Nint,2)
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double precision , intent(out) :: c_pert(N_st),e_2_pert(N_st),H_pert_diag
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`psi_ref`
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bitstring of the determinants present in the various `N_st` states
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`psi_ref_coefs`
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coefficients of the determinants on the various `N_st` states
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`E_refs`
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Energy of the various `N_st` states
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`det_pert`
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Perturber determinant
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`c_pert`
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Perturbative coefficients for the various states
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`e_2_pert`
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Perturbative energetic contribution for the various states
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`H_pert_diag`
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Diagonal |H| matrix element of the perturber
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`Nint`
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Should be equal to `N_int`
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`Ndet`
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Number of determinants `i` in |Psi| on which we apply <det_pert | |H| | `i`>
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`N_st`
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Number of states
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