mirror of
https://github.com/QuantumPackage/qp2.git
synced 2024-12-26 05:13:30 +01:00
484 lines
17 KiB
Fortran
484 lines
17 KiB
Fortran
|
|
subroutine double_htilde_mu_mat_fock_bi_ortho(Nint, key_j, key_i, hmono, htwoe, hthree, 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) :: 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
|
|
|
|
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)
|
|
if(three_body_h_tc.and.elec_num.gt.2)then
|
|
if(.not.double_normal_ord.and.three_e_5_idx_term)then
|
|
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
|
|
htwoe += normal_two_body_bi_orth(p2,h2,p1,h1)
|
|
endif
|
|
endif
|
|
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)
|
|
if(three_body_h_tc.and.elec_num.gt.2)then
|
|
if(.not.double_normal_ord.and.three_e_5_idx_term)then
|
|
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
|
|
htwoe -= normal_two_body_bi_orth(h2,p1,h1,p2)
|
|
htwoe += normal_two_body_bi_orth(h1,p1,h2,p2)
|
|
endif
|
|
endif
|
|
endif
|
|
hthree *= phase
|
|
htwoe *= phase
|
|
htot = htwoe + hthree
|
|
|
|
end
|
|
|
|
|
|
|
|
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
|
|
|
|
|
|
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
|
|
ASSERT (tmp(2) == nexc(2)) ! Number of particle beta
|
|
!DIR$ FORCEINLINE
|
|
call bitstring_to_list_ab(hole, occ_hole, tmp, N_int)
|
|
ASSERT (tmp(1) == nexc(1)) ! Number of holes alpha
|
|
ASSERT (tmp(2) == nexc(2)) ! Number of holes beta
|
|
if(s1==s2.and.s1==1)then
|
|
!!!!!!!!!!!!!!!!!!!!!!!!!! alpha/alpha double exc
|
|
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
|
|
!!!!!!!!!!!!! Holes and particles !!!!!!!!!!!!!!!!!!!!!!!
|
|
ispin = 1 ! i==alpha ==> pure same spin terms
|
|
do i = 1, nexc(ispin) ! number of couple of holes/particles
|
|
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
|
|
do i = 1, nexc(ispin) ! number of couple of holes/particles
|
|
! 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)
|
|
! 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)
|
|
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_exch12_bi_ort(ihole,p2,h2,p1,h1)
|
|
exchange_int = three_e_5_idx_direct_bi_ort(ihole,p2,h1,p1,h2)
|
|
hthree -= direct_int - exchange_int
|
|
enddo
|
|
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
|
|
elseif(s1==s2.and.s1==2)then
|
|
!!!!!!!!!!!!!!!!!!!!!!!!!! beta/beta double exc
|
|
hthree = eff_2_e_from_3_e_bb(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
|
|
!!!!!!!!!!!!! Holes and particles !!!!!!!!!!!!!!!!!!!!!!!
|
|
ispin = 2 ! i==beta ==> pure same spin terms
|
|
do i = 1, nexc(ispin) ! number of couple of holes/particles
|
|
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
|
|
do i = 1, nexc(ispin) ! number of couple of holes/particles
|
|
! 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)
|
|
! 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)
|
|
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_exch12_bi_ort(ihole,p2,h2,p1,h1)
|
|
exchange_int = three_e_5_idx_direct_bi_ort(ihole,p2,h1,p1,h2)
|
|
hthree -= direct_int - exchange_int
|
|
enddo
|
|
else ! (h1,p1) == alpha/(h2,p2) == beta
|
|
hthree = eff_2_e_from_3_e_ab(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
|
|
!!!!!!!!!!!!! Holes and particles !!!!!!!!!!!!!!!!!!!!!!!
|
|
ispin = 1 ! i==alpha ==> alpha/beta/alpha terms
|
|
do i = 1, nexc(ispin) ! number of couple of holes/particles
|
|
! 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
|
|
ispin = 2 ! i==beta ==> alpha/beta/beta terms
|
|
do i = 1, nexc(ispin) ! number of couple of holes/particles
|
|
! 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
|
|
! eff_2_e_from_3_e_ab(p2,p1,h2,h1) = Effective Two-electron operator for alpha/beta double excitations
|
|
!
|
|
! 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) &
|
|
!$OMP PRIVATE (hh1, h1, hh2, h2, pp1, p1, pp2, p2, contrib) &
|
|
!$OMP SHARED (n_act_orb, list_act, Ne,occ, eff_2_e_from_3_e_ab)
|
|
!$OMP DO SCHEDULE (static)
|
|
do hh1 = 1, n_act_orb !! alpha
|
|
h1 = list_act(hh1)
|
|
do hh2 = 1, n_act_orb !! beta
|
|
h2 = list_act(hh2)
|
|
do pp1 = 1, n_act_orb !! alpha
|
|
p1 = list_act(pp1)
|
|
do pp2 = 1, n_act_orb !! beta
|
|
p2 = list_act(pp2)
|
|
call give_contrib_for_abab(h1,h2,p1,p2,occ,Ne,contrib)
|
|
eff_2_e_from_3_e_ab(p2,p1,h2,h1) = contrib
|
|
enddo
|
|
enddo
|
|
enddo
|
|
enddo
|
|
!$OMP END DO
|
|
!$OMP END PARALLEL
|
|
|
|
END_PROVIDER
|
|
|
|
subroutine give_contrib_for_abab(h1,h2,p1,p2,occ,Ne,contrib)
|
|
implicit none
|
|
BEGIN_DOC
|
|
! gives the contribution for a double excitation (h1,p1)_alpha (h2,p2)_beta
|
|
!
|
|
! on top of a determinant whose occupied orbitals is in (occ, Ne)
|
|
END_DOC
|
|
integer, intent(in) :: h1,h2,p1,p2,occ(N_int*bit_kind_size,2),Ne(2)
|
|
double precision, intent(out) :: contrib
|
|
integer :: mm,m
|
|
double precision :: direct_int, exchange_int
|
|
!! h1,p1 == alpha
|
|
!! h2,p2 == beta
|
|
contrib = 0.d0
|
|
do mm = 1, Ne(1) !! alpha
|
|
m = occ(mm,1)
|
|
direct_int = three_e_5_idx_direct_bi_ort(mm,p2,h2,p1,h1)
|
|
! exchange between (h1,p1) and m
|
|
exchange_int = three_e_5_idx_exch13_bi_ort(mm,p2,h2,p1,h1)
|
|
contrib += direct_int - exchange_int
|
|
enddo
|
|
|
|
do mm = 1, Ne(2) !! beta
|
|
m = occ(mm,2)
|
|
direct_int = three_e_5_idx_direct_bi_ort(mm,p2,h2,p1,h1)
|
|
! exchange between (h2,p2) and m
|
|
exchange_int = three_e_5_idx_exch23_bi_ort(mm,p2,h2,p1,h1)
|
|
contrib += direct_int - exchange_int
|
|
enddo
|
|
end
|
|
|
|
BEGIN_PROVIDER [ double precision, eff_2_e_from_3_e_aa, (mo_num, mo_num, mo_num, mo_num)]
|
|
implicit none
|
|
BEGIN_DOC
|
|
! eff_2_e_from_3_e_ab(p2,p1,h2,h1) = Effective Two-electron operator for alpha/alpha double excitations
|
|
!
|
|
! from contractionelec_alpha_num with HF density = a^{dagger}_p1_alpha a^{dagger}_p2_alpha a_h2_alpha a_h1_alpha
|
|
!
|
|
! WARNING :: to be coherent with the phase convention used in the Hamiltonian matrix elements, you must fulfill
|
|
!
|
|
! |||| h2>h1, p2>p1 ||||
|
|
END_DOC
|
|
integer :: i,h1,p1,h2,p2
|
|
integer :: hh1,hh2,pp1,pp2,m,mm
|
|
integer :: Ne(2)
|
|
integer, allocatable :: occ(:,:)
|
|
double precision :: contrib
|
|
allocate( occ(N_int*bit_kind_size,2) )
|
|
call bitstring_to_list_ab(ref_bitmask,occ,Ne,N_int)
|
|
call give_contrib_for_aaaa(1 ,1 ,1 ,1 ,occ,Ne,contrib)
|
|
eff_2_e_from_3_e_aa = 100000000.d0
|
|
!$OMP PARALLEL &
|
|
!$OMP DEFAULT (NONE) &
|
|
!$OMP PRIVATE (hh1, h1, hh2, h2, pp1, p1, pp2, p2, contrib) &
|
|
!$OMP SHARED (n_act_orb, list_act, Ne,occ, eff_2_e_from_3_e_aa)
|
|
!$OMP DO SCHEDULE (static)
|
|
do hh1 = 1, n_act_orb !! alpha
|
|
h1 = list_act(hh1)
|
|
do hh2 = hh1+1, n_act_orb !! alpha
|
|
h2 = list_act(hh2)
|
|
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
|
|
|
|
END_PROVIDER
|
|
|
|
subroutine give_contrib_for_aaaa(h1,h2,p1,p2,occ,Ne,contrib)
|
|
implicit none
|
|
BEGIN_DOC
|
|
! 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
|
|
integer :: mm,m
|
|
double precision :: direct_int, exchange_int
|
|
!! h1,p1 == alpha
|
|
!! 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)
|
|
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)
|
|
exchange_int = three_e_5_idx_direct_bi_ort(mm,p2,h1,p1,h2)
|
|
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
|
|
! eff_2_e_from_3_e_ab(p2,p1,h2,h1) = Effective Two-electron operator for beta/beta double excitations
|
|
!
|
|
! from contractionelec_beta_num with HF density = a^{dagger}_p1_beta a^{dagger}_p2_beta a_h2_beta a_h1_beta
|
|
!
|
|
! WARNING :: to be coherent with the phase convention used in the Hamiltonian matrix elements, you must fulfill
|
|
!
|
|
! |||| 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) &
|
|
!$OMP PRIVATE (hh1, h1, hh2, h2, pp1, p1, pp2, p2, contrib) &
|
|
!$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)
|
|
exchange_int = three_e_5_idx_direct_bi_ort(mm,p2,h1,p1,h2)
|
|
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
|
|
|