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478 lines
17 KiB
Fortran
478 lines
17 KiB
Fortran
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subroutine double_htilde_mu_mat_fock_bi_ortho(Nint, key_j, key_i, hmono, htwoe, hthree, htot)
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BEGIN_DOC
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! <key_j | H_tilde | key_i> for double excitation ONLY FOR ONE- AND TWO-BODY TERMS
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!!
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!! WARNING !!
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!
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! Non hermitian !!
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END_DOC
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use bitmasks
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implicit none
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integer, intent(in) :: Nint
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integer(bit_kind), intent(in) :: key_j(Nint,2), key_i(Nint,2)
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double precision, intent(out) :: hmono, htwoe, hthree, htot
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integer :: occ(Nint*bit_kind_size,2)
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integer :: Ne(2), i, j, ii, jj, ispin, jspin, k, kk
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integer :: degree,exc(0:2,2,2)
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integer :: h1, p1, h2, p2, s1, s2
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double precision :: get_mo_two_e_integral_tc_int,phase
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call get_excitation_degree(key_i, key_j, degree, Nint)
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hmono = 0.d0
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htwoe = 0.d0
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hthree = 0.d0
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htot = 0.d0
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if(degree.ne.2)then
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return
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endif
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integer :: degree_i,degree_j
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call get_excitation_degree(ref_bitmask,key_i,degree_i,N_int)
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call get_excitation_degree(ref_bitmask,key_j,degree_j,N_int)
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call get_double_excitation(key_i, key_j, exc, phase, Nint)
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call decode_exc(exc, 2, h1, p1, h2, p2, s1, s2)
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if(s1.ne.s2)then
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! opposite spin two-body
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htwoe = mo_bi_ortho_tc_two_e(p2,p1,h2,h1)
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if(three_body_h_tc.and.elec_num.gt.2)then
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if(.not.double_normal_ord.and.three_e_5_idx_term)then
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if(degree_i>degree_j)then
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call three_comp_two_e_elem(key_j,h1,h2,p1,p2,s1,s2,hthree)
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else
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call three_comp_two_e_elem(key_i,h1,h2,p1,p2,s1,s2,hthree)
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endif
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elseif(double_normal_ord)then
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htwoe += normal_two_body_bi_orth(p2,h2,p1,h1)
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endif
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endif
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else
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! same spin two-body
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! direct terms
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htwoe = mo_bi_ortho_tc_two_e(p2,p1,h2,h1)
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! exchange terms
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htwoe -= mo_bi_ortho_tc_two_e(p1,p2,h2,h1)
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if(three_body_h_tc.and.elec_num.gt.2)then
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if(.not.double_normal_ord.and.three_e_5_idx_term)then
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if(degree_i>degree_j)then
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call three_comp_two_e_elem(key_j,h1,h2,p1,p2,s1,s2,hthree)
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else
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call three_comp_two_e_elem(key_i,h1,h2,p1,p2,s1,s2,hthree)
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endif
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elseif(double_normal_ord)then
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htwoe -= normal_two_body_bi_orth(h2,p1,h1,p2)
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htwoe += normal_two_body_bi_orth(h1,p1,h2,p2)
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endif
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endif
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endif
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hthree *= phase
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htwoe *= phase
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htot = htwoe + hthree
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end
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subroutine three_comp_two_e_elem(key_i,h1,h2,p1,p2,s1,s2,hthree)
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implicit none
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integer(bit_kind), intent(in) :: key_i(N_int,2)
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integer, intent(in) :: h1,h2,p1,p2,s1,s2
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double precision, intent(out) :: hthree
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integer :: nexc(2),i,ispin,na,nb
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integer(bit_kind) :: hole(N_int,2)
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integer(bit_kind) :: particle(N_int,2)
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integer :: occ_hole(N_int*bit_kind_size,2)
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integer :: occ_particle(N_int*bit_kind_size,2)
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integer :: n_occ_ab_hole(2),n_occ_ab_particle(2)
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integer(bit_kind) :: det_tmp(N_int,2)
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integer :: ipart, ihole
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double precision :: direct_int, exchange_int
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nexc(1) = 0
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nexc(2) = 0
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!! Get all the holes and particles of key_i with respect to the ROHF determinant
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do i=1,N_int
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hole(i,1) = xor(key_i(i,1),ref_bitmask(i,1))
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hole(i,2) = xor(key_i(i,2),ref_bitmask(i,2))
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particle(i,1) = iand(hole(i,1),key_i(i,1))
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particle(i,2) = iand(hole(i,2),key_i(i,2))
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hole(i,1) = iand(hole(i,1),ref_bitmask(i,1))
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hole(i,2) = iand(hole(i,2),ref_bitmask(i,2))
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nexc(1) = nexc(1) + popcnt(hole(i,1))
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nexc(2) = nexc(2) + popcnt(hole(i,2))
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enddo
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integer :: tmp(2)
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!DIR$ FORCEINLINE
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call bitstring_to_list_ab(particle, occ_particle, tmp, N_int)
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ASSERT (tmp(1) == nexc(1)) ! Number of particles alpha
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ASSERT (tmp(2) == nexc(2)) ! Number of particle beta
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!DIR$ FORCEINLINE
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call bitstring_to_list_ab(hole, occ_hole, tmp, N_int)
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ASSERT (tmp(1) == nexc(1)) ! Number of holes alpha
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ASSERT (tmp(2) == nexc(2)) ! Number of holes beta
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if(s1==s2.and.s1==1)then
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!!!!!!!!!!!!!!!!!!!!!!!!!! alpha/alpha double exc
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hthree = eff_2_e_from_3_e_aa(p2,p1,h2,h1)
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if(nexc(1)+nexc(2) ==0)return !! if you're on the reference determinant
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!!!!!!!! the matrix element is already exact
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!!!!!!!! else you need to take care of holes and particles
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!!!!!!!!!!!!! Holes and particles !!!!!!!!!!!!!!!!!!!!!!!
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ispin = 1 ! i==alpha ==> pure same spin terms
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do i = 1, nexc(ispin) ! number of couple of holes/particles
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ipart=occ_particle(i,ispin)
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hthree += three_e_double_parrallel_spin_prov(ipart,p2,h2,p1,h1)
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ihole=occ_hole(i,ispin)
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hthree -= three_e_double_parrallel_spin_prov(ihole,p2,h2,p1,h1)
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enddo
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ispin = 2 ! i==beta ==> alpha/alpha/beta terms
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do i = 1, nexc(ispin) ! number of couple of holes/particles
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! exchange between (h1,p1) and (h2,p2)
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ipart=occ_particle(i,ispin)
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direct_int = three_e_5_idx_direct_bi_ort(ipart,p2,h2,p1,h1)
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exchange_int = three_e_5_idx_exch12_bi_ort(ipart,p2,h2,p1,h1)
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hthree += direct_int - exchange_int
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ihole=occ_hole(i,ispin)
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direct_int = three_e_5_idx_direct_bi_ort(ihole,p2,h2,p1,h1)
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exchange_int = three_e_5_idx_exch12_bi_ort(ihole,p2,h2,p1,h1)
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hthree -= direct_int - exchange_int
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enddo
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!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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elseif(s1==s2.and.s1==2)then
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!!!!!!!!!!!!!!!!!!!!!!!!!! beta/beta double exc
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hthree = eff_2_e_from_3_e_bb(p2,p1,h2,h1)
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if(nexc(1)+nexc(2) ==0)return !! if you're on the reference determinant
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!!!!!!!! the matrix element is already exact
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!!!!!!!! else you need to take care of holes and particles
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!!!!!!!!!!!!! Holes and particles !!!!!!!!!!!!!!!!!!!!!!!
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ispin = 2 ! i==beta ==> pure same spin terms
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do i = 1, nexc(ispin) ! number of couple of holes/particles
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ipart=occ_particle(i,ispin)
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hthree += three_e_double_parrallel_spin_prov(ipart,p2,h2,p1,h1)
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ihole=occ_hole(i,ispin)
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hthree -= three_e_double_parrallel_spin_prov(ihole,p2,h2,p1,h1)
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enddo
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ispin = 1 ! i==alpha==> beta/beta/alpha terms
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do i = 1, nexc(ispin) ! number of couple of holes/particles
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! exchange between (h1,p1) and (h2,p2)
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ipart=occ_particle(i,ispin)
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direct_int = three_e_5_idx_direct_bi_ort(ipart,p2,h2,p1,h1)
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exchange_int = three_e_5_idx_exch12_bi_ort(ipart,p2,h2,p1,h1)
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hthree += direct_int - exchange_int
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ihole=occ_hole(i,ispin)
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direct_int = three_e_5_idx_direct_bi_ort(ihole,p2,h2,p1,h1)
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exchange_int = three_e_5_idx_exch12_bi_ort(ihole,p2,h2,p1,h1)
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hthree -= direct_int - exchange_int
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enddo
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else ! (h1,p1) == alpha/(h2,p2) == beta
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hthree = eff_2_e_from_3_e_ab(p2,p1,h2,h1)
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if(nexc(1)+nexc(2) ==0)return !! if you're on the reference determinant
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!!!!!!!! the matrix element is already exact
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!!!!!!!! else you need to take care of holes and particles
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!!!!!!!!!!!!! Holes and particles !!!!!!!!!!!!!!!!!!!!!!!
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ispin = 1 ! i==alpha ==> alpha/beta/alpha terms
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do i = 1, nexc(ispin) ! number of couple of holes/particles
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! exchange between (h1,p1) and i
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ipart=occ_particle(i,ispin)
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direct_int = three_e_5_idx_direct_bi_ort(ipart,p2,h2,p1,h1)
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exchange_int = three_e_5_idx_exch13_bi_ort(ipart,p2,h2,p1,h1)
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hthree += direct_int - exchange_int
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ihole=occ_hole(i,ispin)
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direct_int = three_e_5_idx_direct_bi_ort(ihole,p2,h2,p1,h1)
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exchange_int = three_e_5_idx_exch13_bi_ort(ihole,p2,h2,p1,h1)
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hthree -= direct_int - exchange_int
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enddo
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ispin = 2 ! i==beta ==> alpha/beta/beta terms
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do i = 1, nexc(ispin) ! number of couple of holes/particles
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! exchange between (h2,p2) and i
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ipart=occ_particle(i,ispin)
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direct_int = three_e_5_idx_direct_bi_ort(ipart,p2,h2,p1,h1)
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exchange_int = three_e_5_idx_exch23_bi_ort(ipart,p2,h2,p1,h1)
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hthree += direct_int - exchange_int
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ihole=occ_hole(i,ispin)
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direct_int = three_e_5_idx_direct_bi_ort(ihole,p2,h2,p1,h1)
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exchange_int = three_e_5_idx_exch23_bi_ort(ihole,p2,h2,p1,h1)
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hthree -= direct_int - exchange_int
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enddo
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endif
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end
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BEGIN_PROVIDER [ double precision, eff_2_e_from_3_e_ab, (mo_num, mo_num, mo_num, mo_num)]
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implicit none
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BEGIN_DOC
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! eff_2_e_from_3_e_ab(p2,p1,h2,h1) = Effective Two-electron operator for alpha/beta double excitations
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!
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! from contraction with HF density = a^{dagger}_p1_alpha a^{dagger}_p2_beta a_h2_beta a_h1_alpha
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END_DOC
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integer :: i,h1,p1,h2,p2
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integer :: hh1,hh2,pp1,pp2,m,mm
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integer :: Ne(2)
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integer, allocatable :: occ(:,:)
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double precision :: contrib
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allocate( occ(N_int*bit_kind_size,2) )
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call bitstring_to_list_ab(ref_bitmask,occ,Ne,N_int)
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call give_contrib_for_abab(1,1,1,1,occ,Ne,contrib)
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eff_2_e_from_3_e_ab = 0.d0
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!$OMP PARALLEL &
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!$OMP DEFAULT (NONE) &
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!$OMP PRIVATE (hh1, h1, hh2, h2, pp1, p1, pp2, p2, contrib) &
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!$OMP SHARED (n_act_orb, list_act, Ne,occ, eff_2_e_from_3_e_ab)
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!$OMP DO SCHEDULE (static)
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do hh1 = 1, n_act_orb !! alpha
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h1 = list_act(hh1)
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do hh2 = 1, n_act_orb !! beta
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h2 = list_act(hh2)
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do pp1 = 1, n_act_orb !! alpha
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p1 = list_act(pp1)
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do pp2 = 1, n_act_orb !! beta
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p2 = list_act(pp2)
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call give_contrib_for_abab(h1,h2,p1,p2,occ,Ne,contrib)
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eff_2_e_from_3_e_ab(p2,p1,h2,h1) = contrib
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enddo
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enddo
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enddo
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enddo
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!$OMP END DO
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!$OMP END PARALLEL
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END_PROVIDER
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subroutine give_contrib_for_abab(h1,h2,p1,p2,occ,Ne,contrib)
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implicit none
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BEGIN_DOC
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! gives the contribution for a double excitation (h1,p1)_alpha (h2,p2)_beta
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!
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! on top of a determinant whose occupied orbitals is in (occ, Ne)
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END_DOC
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integer, intent(in) :: h1,h2,p1,p2,occ(N_int*bit_kind_size,2),Ne(2)
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double precision, intent(out) :: contrib
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integer :: mm,m
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double precision :: direct_int, exchange_int
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!! h1,p1 == alpha
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!! h2,p2 == beta
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contrib = 0.d0
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do mm = 1, Ne(1) !! alpha
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m = occ(mm,1)
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direct_int = three_e_5_idx_direct_bi_ort(mm,p2,h2,p1,h1)
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! exchange between (h1,p1) and m
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exchange_int = three_e_5_idx_exch13_bi_ort(mm,p2,h2,p1,h1)
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contrib += direct_int - exchange_int
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enddo
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do mm = 1, Ne(2) !! beta
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m = occ(mm,2)
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direct_int = three_e_5_idx_direct_bi_ort(mm,p2,h2,p1,h1)
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! exchange between (h2,p2) and m
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exchange_int = three_e_5_idx_exch23_bi_ort(mm,p2,h2,p1,h1)
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contrib += direct_int - exchange_int
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enddo
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end
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BEGIN_PROVIDER [ double precision, eff_2_e_from_3_e_aa, (mo_num, mo_num, mo_num, mo_num)]
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implicit none
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BEGIN_DOC
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! eff_2_e_from_3_e_ab(p2,p1,h2,h1) = Effective Two-electron operator for alpha/alpha double excitations
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!
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! from contractionelec_alpha_num with HF density = a^{dagger}_p1_alpha a^{dagger}_p2_alpha a_h2_alpha a_h1_alpha
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!
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! WARNING :: to be coherent with the phase convention used in the Hamiltonian matrix elements, you must fulfill
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!
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! |||| h2>h1, p2>p1 ||||
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END_DOC
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integer :: i,h1,p1,h2,p2
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integer :: hh1,hh2,pp1,pp2,m,mm
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integer :: Ne(2)
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integer, allocatable :: occ(:,:)
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double precision :: contrib
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allocate( occ(N_int*bit_kind_size,2) )
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call bitstring_to_list_ab(ref_bitmask,occ,Ne,N_int)
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call give_contrib_for_aaaa(1 ,1 ,1 ,1 ,occ,Ne,contrib)
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eff_2_e_from_3_e_aa = 100000000.d0
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!$OMP PARALLEL &
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!$OMP DEFAULT (NONE) &
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!$OMP PRIVATE (hh1, h1, hh2, h2, pp1, p1, pp2, p2, contrib) &
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!$OMP SHARED (n_act_orb, list_act, Ne,occ, eff_2_e_from_3_e_aa)
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!$OMP DO SCHEDULE (static)
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do hh1 = 1, n_act_orb !! alpha
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h1 = list_act(hh1)
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do hh2 = hh1+1, n_act_orb !! alpha
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h2 = list_act(hh2)
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do pp1 = 1, n_act_orb !! alpha
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p1 = list_act(pp1)
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do pp2 = pp1+1, n_act_orb !! alpha
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p2 = list_act(pp2)
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call give_contrib_for_aaaa(h1,h2,p1,p2,occ,Ne,contrib)
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eff_2_e_from_3_e_aa(p2,p1,h2,h1) = contrib
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enddo
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enddo
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enddo
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enddo
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!$OMP END DO
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!$OMP END PARALLEL
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END_PROVIDER
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subroutine give_contrib_for_aaaa(h1,h2,p1,p2,occ,Ne,contrib)
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implicit none
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BEGIN_DOC
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! gives the contribution for a double excitation (h1,p1)_alpha (h2,p2)_alpha
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!
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! on top of a determinant whose occupied orbitals is in (occ, Ne)
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END_DOC
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integer, intent(in) :: h1,h2,p1,p2,occ(N_int*bit_kind_size,2),Ne(2)
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double precision, intent(out) :: contrib
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integer :: mm,m
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double precision :: direct_int, exchange_int
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!! h1,p1 == alpha
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!! h2,p2 == alpha
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contrib = 0.d0
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do mm = 1, Ne(1) !! alpha ==> pure parallele spin contribution
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m = occ(mm,1)
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contrib += three_e_double_parrallel_spin_prov(m,p2,h2,p1,h1)
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enddo
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do mm = 1, Ne(2) !! beta
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m = occ(mm,2)
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direct_int = three_e_5_idx_direct_bi_ort(mm,p2,h2,p1,h1)
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! exchange between (h1,p1) and (h2,p2)
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exchange_int = three_e_5_idx_exch12_bi_ort(mm,p2,h2,p1,h1)
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contrib += direct_int - exchange_int
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enddo
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end
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BEGIN_PROVIDER [ double precision, eff_2_e_from_3_e_bb, (mo_num, mo_num, mo_num, mo_num)]
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implicit none
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BEGIN_DOC
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! eff_2_e_from_3_e_ab(p2,p1,h2,h1) = Effective Two-electron operator for beta/beta double excitations
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!
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! from contractionelec_beta_num with HF density = a^{dagger}_p1_beta a^{dagger}_p2_beta a_h2_beta a_h1_beta
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!
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! WARNING :: to be coherent with the phase convention used in the Hamiltonian matrix elements, you must fulfill
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!
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! |||| h2>h1, p2>p1 ||||
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END_DOC
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integer :: i,h1,p1,h2,p2
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integer :: hh1,hh2,pp1,pp2,m,mm
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integer :: Ne(2)
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integer, allocatable :: occ(:,:)
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double precision :: contrib
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allocate( occ(N_int*bit_kind_size,2) )
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call bitstring_to_list_ab(ref_bitmask,occ,Ne,N_int)
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call give_contrib_for_bbbb(1,1 ,1 ,1 ,occ,Ne,contrib)
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eff_2_e_from_3_e_bb = 100000000.d0
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!$OMP PARALLEL &
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!$OMP DEFAULT (NONE) &
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!$OMP PRIVATE (hh1, h1, hh2, h2, pp1, p1, pp2, p2, contrib) &
|
||
!$OMP SHARED (n_act_orb, list_act, Ne,occ, eff_2_e_from_3_e_bb)
|
||
!$OMP DO SCHEDULE (static)
|
||
do hh1 = 1, n_act_orb !! beta
|
||
h1 = list_act(hh1)
|
||
do hh2 = hh1+1, n_act_orb !! beta
|
||
h2 = list_act(hh2)
|
||
do pp1 = 1, n_act_orb !! beta
|
||
p1 = list_act(pp1)
|
||
do pp2 = pp1+1, n_act_orb !! beta
|
||
p2 = list_act(pp2)
|
||
call give_contrib_for_bbbb(h1,h2,p1,p2,occ,Ne,contrib)
|
||
eff_2_e_from_3_e_bb(p2,p1,h2,h1) = contrib
|
||
enddo
|
||
enddo
|
||
enddo
|
||
enddo
|
||
!$OMP END DO
|
||
!$OMP END PARALLEL
|
||
|
||
END_PROVIDER
|
||
|
||
subroutine give_contrib_for_bbbb(h1,h2,p1,p2,occ,Ne,contrib)
|
||
implicit none
|
||
BEGIN_DOC
|
||
! gives the contribution for a double excitation (h1,p1)_beta (h2,p2)_beta
|
||
!
|
||
! on top of a determinant whose occupied orbitals is in (occ, Ne)
|
||
END_DOC
|
||
integer, intent(in) :: h1,h2,p1,p2,occ(N_int*bit_kind_size,2),Ne(2)
|
||
double precision, intent(out) :: contrib
|
||
integer :: mm,m
|
||
double precision :: direct_int, exchange_int
|
||
!! h1,p1 == beta
|
||
!! h2,p2 == beta
|
||
contrib = 0.d0
|
||
do mm = 1, Ne(2) !! beta ==> pure parallele spin contribution
|
||
m = occ(mm,1)
|
||
contrib += three_e_double_parrallel_spin_prov(m,p2,h2,p1,h1)
|
||
enddo
|
||
|
||
do mm = 1, Ne(1) !! alpha
|
||
m = occ(mm,1)
|
||
direct_int = three_e_5_idx_direct_bi_ort(mm,p2,h2,p1,h1)
|
||
! exchange between (h1,p1) and (h2,p2)
|
||
exchange_int = three_e_5_idx_exch12_bi_ort(mm,p2,h2,p1,h1)
|
||
contrib += direct_int - exchange_int
|
||
enddo
|
||
end
|
||
|
||
|
||
subroutine double_htilde_mu_mat_fock_bi_ortho_no_3e(Nint, key_j, key_i, htot)
|
||
|
||
BEGIN_DOC
|
||
! <key_j | H_tilde | key_i> for double excitation ONLY FOR ONE- AND TWO-BODY TERMS
|
||
!!
|
||
!! WARNING !!
|
||
!
|
||
! Non hermitian !!
|
||
END_DOC
|
||
|
||
use bitmasks
|
||
|
||
implicit none
|
||
integer, intent(in) :: Nint
|
||
integer(bit_kind), intent(in) :: key_j(Nint,2), key_i(Nint,2)
|
||
double precision, intent(out) :: htot
|
||
double precision :: hmono, htwoe
|
||
integer :: occ(Nint*bit_kind_size,2)
|
||
integer :: Ne(2), i, j, ii, jj, ispin, jspin, k, kk
|
||
integer :: degree,exc(0:2,2,2)
|
||
integer :: h1, p1, h2, p2, s1, s2
|
||
double precision :: get_mo_two_e_integral_tc_int,phase
|
||
|
||
|
||
call get_excitation_degree(key_i, key_j, degree, Nint)
|
||
|
||
hmono = 0.d0
|
||
htwoe = 0.d0
|
||
htot = 0.d0
|
||
|
||
if(degree.ne.2)then
|
||
return
|
||
endif
|
||
integer :: degree_i,degree_j
|
||
call get_excitation_degree(ref_bitmask,key_i,degree_i,N_int)
|
||
call get_excitation_degree(ref_bitmask,key_j,degree_j,N_int)
|
||
call get_double_excitation(key_i, key_j, exc, phase, Nint)
|
||
call decode_exc(exc, 2, h1, p1, h2, p2, s1, s2)
|
||
|
||
if(s1.ne.s2)then
|
||
! opposite spin two-body
|
||
htwoe = mo_bi_ortho_tc_two_e(p2,p1,h2,h1)
|
||
else
|
||
! same spin two-body
|
||
! direct terms
|
||
htwoe = mo_bi_ortho_tc_two_e(p2,p1,h2,h1)
|
||
! exchange terms
|
||
htwoe -= mo_bi_ortho_tc_two_e(p1,p2,h2,h1)
|
||
endif
|
||
htwoe *= phase
|
||
htot = htwoe
|
||
|
||
end
|
||
|