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qp2/plugins/local/tc_bi_ortho/slater_tc_opt_double.irp.f

508 lines
17 KiB
Fortran
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! ---
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subroutine double_htilde_mu_mat_fock_bi_ortho(Nint, key_j, key_i, hmono, htwoe, hthree, htot)
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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!!
!! WARNING !!
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!
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! Non hermitian !!
END_DOC
use bitmasks
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)
double precision, intent(out) :: hmono, htwoe, hthree, htot
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
hthree = 0.d0
htot = 0.d0
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if(degree .ne. 2) then
return
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endif
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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)
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call get_double_excitation(key_i, key_j, exc, phase, Nint)
call decode_exc(exc, 2, h1, p1, h2, p2, s1, s2)
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if(s1 .ne. s2) then
! opposite spin two-body
htwoe = mo_bi_ortho_tc_two_e(p2,p1,h2,h1)
if(three_body_h_tc .and. (elec_num .gt. 2)) then
! add 3-e term
if(.not.double_normal_ord .and. three_e_5_idx_term) then
! 5-idx approx
if(degree_i > degree_j) then
call three_comp_two_e_elem(key_j,h1,h2,p1,p2,s1,s2,hthree)
else
call three_comp_two_e_elem(key_i,h1,h2,p1,p2,s1,s2,hthree)
endif
elseif(double_normal_ord) then
! noL a la Manu
htwoe += normal_two_body_bi_orth(p2,h2,p1,h1)
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endif
endif
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else
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! 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)
if(three_body_h_tc .and. (elec_num .gt. 2)) then
! add 3-e term
if(.not.double_normal_ord.and.three_e_5_idx_term)then
! 5-idx approx
if(degree_i > degree_j) then
call three_comp_two_e_elem(key_j,h1,h2,p1,p2,s1,s2,hthree)
else
call three_comp_two_e_elem(key_i,h1,h2,p1,p2,s1,s2,hthree)
endif
elseif(double_normal_ord) then
! noL a la Manu
htwoe -= normal_two_body_bi_orth(h2,p1,h1,p2)
htwoe += normal_two_body_bi_orth(h1,p1,h2,p2)
endif
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endif
endif
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hthree *= phase
htwoe *= phase
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htot = htwoe + hthree
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end
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! ---
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subroutine three_comp_two_e_elem(key_i,h1,h2,p1,p2,s1,s2,hthree)
implicit none
integer(bit_kind), intent(in) :: key_i(N_int,2)
integer, intent(in) :: h1,h2,p1,p2,s1,s2
double precision, intent(out) :: hthree
integer :: nexc(2),i,ispin,na,nb
integer(bit_kind) :: hole(N_int,2)
integer(bit_kind) :: particle(N_int,2)
integer :: occ_hole(N_int*bit_kind_size,2)
integer :: occ_particle(N_int*bit_kind_size,2)
integer :: n_occ_ab_hole(2),n_occ_ab_particle(2)
integer(bit_kind) :: det_tmp(N_int,2)
integer :: ipart, ihole
double precision :: direct_int, exchange_int
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nexc(1) = 0
nexc(2) = 0
!! Get all the holes and particles of key_i with respect to the ROHF determinant
do i=1,N_int
hole(i,1) = xor(key_i(i,1),ref_bitmask(i,1))
hole(i,2) = xor(key_i(i,2),ref_bitmask(i,2))
particle(i,1) = iand(hole(i,1),key_i(i,1))
particle(i,2) = iand(hole(i,2),key_i(i,2))
hole(i,1) = iand(hole(i,1),ref_bitmask(i,1))
hole(i,2) = iand(hole(i,2),ref_bitmask(i,2))
nexc(1) = nexc(1) + popcnt(hole(i,1))
nexc(2) = nexc(2) + popcnt(hole(i,2))
enddo
integer :: tmp(2)
!DIR$ FORCEINLINE
call bitstring_to_list_ab(particle, occ_particle, tmp, N_int)
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
call bitstring_to_list_ab(hole, occ_hole, tmp, N_int)
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
!!!!!!!!!!!!!!!!!!!!!!!!!! alpha/alpha double exc
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hthree = eff_2_e_from_3_e_aa(p2,p1,h2,h1)
if(nexc(1)+nexc(2) ==0)return !! if you're on the reference determinant
!!!!!!!! the matrix element is already exact
!!!!!!!! else you need to take care of holes and particles
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!!!!!!!!!!!!! Holes and particles !!!!!!!!!!!!!!!!!!!!!!!
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)
hthree += three_e_double_parrallel_spin_prov(ipart,p2,h2,p1,h1)
ihole=occ_hole(i,ispin)
hthree -= three_e_double_parrallel_spin_prov(ihole,p2,h2,p1,h1)
enddo
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)
ipart=occ_particle(i,ispin)
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)
exchange_int = three_e_5_idx_direct_bi_ort(ipart,p2,h1,p1,h2)
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hthree += direct_int - exchange_int
ihole=occ_hole(i,ispin)
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)
exchange_int = three_e_5_idx_direct_bi_ort(ihole,p2,h1,p1,h2)
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hthree -= direct_int - exchange_int
enddo
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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elseif(s1==s2.and.s1==2)then
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!!!!!!!!!!!!!!!!!!!!!!!!!! beta/beta double exc
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
!!!!!!!! the matrix element is already exact
!!!!!!!! else you need to take care of holes and particles
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!!!!!!!!!!!!! Holes and particles !!!!!!!!!!!!!!!!!!!!!!!
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)
hthree += three_e_double_parrallel_spin_prov(ipart,p2,h2,p1,h1)
ihole=occ_hole(i,ispin)
hthree -= three_e_double_parrallel_spin_prov(ihole,p2,h2,p1,h1)
enddo
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)
ipart=occ_particle(i,ispin)
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)
exchange_int = three_e_5_idx_direct_bi_ort(ipart,p2,h1,p1,h2)
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hthree += direct_int - exchange_int
ihole=occ_hole(i,ispin)
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)
exchange_int = three_e_5_idx_direct_bi_ort(ihole,p2,h1,p1,h2)
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hthree -= direct_int - exchange_int
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
!!!!!!!! the matrix element is already exact
!!!!!!!! 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
do i = 1, nexc(ispin) ! number of couple of holes/particles
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! exchange between (h1,p1) and i
ipart=occ_particle(i,ispin)
direct_int = three_e_5_idx_direct_bi_ort(ipart,p2,h2,p1,h1)
exchange_int = three_e_5_idx_exch13_bi_ort(ipart,p2,h2,p1,h1)
hthree += direct_int - exchange_int
ihole=occ_hole(i,ispin)
direct_int = three_e_5_idx_direct_bi_ort(ihole,p2,h2,p1,h1)
exchange_int = three_e_5_idx_exch13_bi_ort(ihole,p2,h2,p1,h1)
hthree -= direct_int - exchange_int
enddo
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ispin = 2 ! i==beta ==> alpha/beta/beta terms
do i = 1, nexc(ispin) ! number of couple of holes/particles
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! exchange between (h2,p2) and i
ipart=occ_particle(i,ispin)
direct_int = three_e_5_idx_direct_bi_ort(ipart,p2,h2,p1,h1)
exchange_int = three_e_5_idx_exch23_bi_ort(ipart,p2,h2,p1,h1)
hthree += direct_int - exchange_int
ihole=occ_hole(i,ispin)
direct_int = three_e_5_idx_direct_bi_ort(ihole,p2,h2,p1,h1)
exchange_int = three_e_5_idx_exch23_bi_ort(ihole,p2,h2,p1,h1)
hthree -= direct_int - exchange_int
enddo
endif
end
BEGIN_PROVIDER [ double precision, eff_2_e_from_3_e_ab, (mo_num, mo_num, mo_num, mo_num)]
implicit none
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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!
! from contraction with HF density = a^{dagger}_p1_alpha a^{dagger}_p2_beta a_h2_beta a_h1_alpha
END_DOC
integer :: i,h1,p1,h2,p2
integer :: hh1,hh2,pp1,pp2,m,mm
integer :: Ne(2)
integer, allocatable :: occ(:,:)
double precision :: contrib
allocate( occ(N_int*bit_kind_size,2) )
call bitstring_to_list_ab(ref_bitmask,occ,Ne,N_int)
call give_contrib_for_abab(1,1,1,1,occ,Ne,contrib)
eff_2_e_from_3_e_ab = 0.d0
!$OMP PARALLEL &
!$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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!$OMP DO SCHEDULE (static)
do hh1 = 1, n_act_orb !! alpha
h1 = list_act(hh1)
do hh2 = 1, n_act_orb !! beta
h2 = list_act(hh2)
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do pp1 = 1, n_act_orb !! alpha
p1 = list_act(pp1)
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do pp2 = 1, n_act_orb !! beta
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p2 = list_act(pp2)
call give_contrib_for_abab(h1,h2,p1,p2,occ,Ne,contrib)
eff_2_e_from_3_e_ab(p2,p1,h2,h1) = contrib
enddo
enddo
enddo
enddo
!$OMP END DO
!$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)
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
!
! 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
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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
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
exchange_int = three_e_5_idx_exch13_bi_ort(mm,p2,h2,p1,h1)
contrib += direct_int - exchange_int
enddo
do mm = 1, Ne(2) !! beta
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
exchange_int = three_e_5_idx_exch23_bi_ort(mm,p2,h2,p1,h1)
contrib += direct_int - exchange_int
enddo
end
BEGIN_PROVIDER [ double precision, eff_2_e_from_3_e_aa, (mo_num, mo_num, mo_num, mo_num)]
implicit none
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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!
! 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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! WARNING :: to be coherent with the phase convention used in the Hamiltonian matrix elements, you must fulfill
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!
! |||| h2>h1, p2>p1 ||||
END_DOC
integer :: i,h1,p1,h2,p2
integer :: hh1,hh2,pp1,pp2,m,mm
integer :: Ne(2)
integer, allocatable :: occ(:,:)
double precision :: contrib
allocate( occ(N_int*bit_kind_size,2) )
call bitstring_to_list_ab(ref_bitmask,occ,Ne,N_int)
call give_contrib_for_aaaa(1 ,1 ,1 ,1 ,occ,Ne,contrib)
eff_2_e_from_3_e_aa = 100000000.d0
!$OMP PARALLEL &
!$OMP DEFAULT (NONE) &
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!$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)
do hh1 = 1, n_act_orb !! alpha
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
p1 = list_act(pp1)
do pp2 = pp1+1, n_act_orb !! alpha
p2 = list_act(pp2)
call give_contrib_for_aaaa(h1,h2,p1,p2,occ,Ne,contrib)
eff_2_e_from_3_e_aa(p2,p1,h2,h1) = contrib
enddo
enddo
enddo
enddo
!$OMP END DO
!$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)
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
!
! 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
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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
contrib = 0.d0
do mm = 1, Ne(1) !! alpha ==> 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(2) !! beta
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)
exchange_int = three_e_5_idx_direct_bi_ort(mm,p2,h1,p1,h2)
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contrib += direct_int - exchange_int
enddo
end
BEGIN_PROVIDER [ double precision, eff_2_e_from_3_e_bb, (mo_num, mo_num, mo_num, mo_num)]
implicit none
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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!
! 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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! WARNING :: to be coherent with the phase convention used in the Hamiltonian matrix elements, you must fulfill
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!
! |||| h2>h1, p2>p1 ||||
END_DOC
integer :: i,h1,p1,h2,p2
integer :: hh1,hh2,pp1,pp2,m,mm
integer :: Ne(2)
integer, allocatable :: occ(:,:)
double precision :: contrib
allocate( occ(N_int*bit_kind_size,2) )
call bitstring_to_list_ab(ref_bitmask,occ,Ne,N_int)
call give_contrib_for_bbbb(1,1 ,1 ,1 ,occ,Ne,contrib)
eff_2_e_from_3_e_bb = 100000000.d0
!$OMP PARALLEL &
!$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_bb)
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!$OMP DO SCHEDULE (static)
do hh1 = 1, n_act_orb !! beta
h1 = list_act(hh1)
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do hh2 = hh1+1, n_act_orb !! beta
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h2 = list_act(hh2)
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do pp1 = 1, n_act_orb !! beta
p1 = list_act(pp1)
do pp2 = pp1+1, n_act_orb !! beta
p2 = list_act(pp2)
call give_contrib_for_bbbb(h1,h2,p1,p2,occ,Ne,contrib)
eff_2_e_from_3_e_bb(p2,p1,h2,h1) = contrib
enddo
enddo
enddo
enddo
!$OMP END DO
!$OMP END PARALLEL
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END_PROVIDER
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subroutine give_contrib_for_bbbb(h1,h2,p1,p2,occ,Ne,contrib)
implicit none
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BEGIN_DOC
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! 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
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integer :: mm,m
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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)
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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)
exchange_int = three_e_5_idx_direct_bi_ort(mm,p2,h1,p1,h2)
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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
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! <key_j |H_tilde | key_i> for double excitation ONLY FOR ONE- AND TWO-BODY TERMS
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!!
!! WARNING !!
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!
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! Non hermitian !!
END_DOC
use bitmasks
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)
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
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! opposite spin two-body
htwoe = mo_bi_ortho_tc_two_e(p2,p1,h2,h1)
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else
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! 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)
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endif
htwoe *= phase
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htot = htwoe
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end