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244 lines
5.2 KiB
Fortran
244 lines
5.2 KiB
Fortran
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! --
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subroutine hmat_bi_ortho(key_j, key_i, Nint, hmono, htwoe, htot)
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BEGIN_DOC
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!
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! < key_j | H | key_i > where | key_j > is developed on the LEFT basis and | key_i > is developed on the RIGHT basis
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!
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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_i(Nint,2), key_j(Nint,2)
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double precision, intent(out) :: hmono, htwoe, htot
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integer :: degree
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hmono = 0.d0
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htwoe = 0.d0
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htot = 0.d0
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call get_excitation_degree(key_i, key_j, degree, Nint)
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if(degree .gt. 2) return
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if(degree == 0) then
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call diag_hmat_bi_ortho(Nint, key_i, hmono, htwoe)
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htot = htot + nuclear_repulsion
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else if (degree == 1) then
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call single_hmat_bi_ortho(Nint, key_j, key_i, hmono, htwoe)
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else if(degree == 2) then
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call double_hmat_bi_ortho(Nint, key_j, key_i, hmono, htwoe)
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endif
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htot += hmono + htwoe
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return
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end subroutine hmat_bi_ortho
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! ---
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subroutine diag_hmat_bi_ortho(Nint, key_i, hmono, htwoe)
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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_i(Nint,2)
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double precision, intent(out) :: hmono, htwoe
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integer :: occ(Nint*bit_kind_size,2)
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integer :: Ne(2), i, j, ii, jj, ispin, jspin
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hmono = 0.d0
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htwoe = 0.d0
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call bitstring_to_list_ab(key_i, occ, Ne, Nint)
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do ispin = 1, 2
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do i = 1, Ne(ispin)
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ii = occ(i,ispin)
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hmono += mo_bi_ortho_one_e(ii,ii)
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enddo
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enddo
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! alpha/beta two-body
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ispin = 1
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jspin = 2
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do i = 1, Ne(ispin) ! electron 1
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ii = occ(i,ispin)
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do j = 1, Ne(jspin) ! electron 2
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jj = occ(j,jspin)
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htwoe += mo_bi_ortho_coul_e(jj,ii,jj,ii)
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enddo
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enddo
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! alpha/alpha two-body
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do i = 1, Ne(ispin)
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ii = occ(i,ispin)
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do j = i+1, Ne(ispin)
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jj = occ(j,ispin)
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htwoe += mo_bi_ortho_coul_e(ii,jj,ii,jj) - mo_bi_ortho_coul_e(ii,jj,jj,ii)
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enddo
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enddo
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! beta/beta two-body
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do i = 1, Ne(jspin)
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ii = occ(i,jspin)
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do j = i+1, Ne(jspin)
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jj = occ(j,jspin)
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htwoe += mo_bi_ortho_coul_e(ii,jj,ii,jj) - mo_bi_ortho_coul_e(ii,jj,jj,ii)
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enddo
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enddo
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return
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end subroutine diag_hmat_bi_ortho
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! ---
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subroutine single_hmat_bi_ortho(Nint, key_j, key_i, hmono, htwoe)
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BEGIN_DOC
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!
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! < key_j | H | key_i > for single excitation
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!
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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
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integer :: occ(Nint*bit_kind_size,2)
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integer :: Ne(2), i, j, ii, ispin, jspin
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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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integer :: other_spin(2)
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double precision :: phase
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other_spin(1) = 2
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other_spin(2) = 1
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hmono = 0.d0
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htwoe = 0.d0
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call get_excitation_degree(key_i, key_j, degree, Nint)
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if(degree .ne. 1) then
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return
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endif
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call bitstring_to_list_ab(key_i, occ, Ne, Nint)
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call get_single_excitation(key_i, key_j, exc, phase, Nint)
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call decode_exc(exc, 1, h1, p1, h2, p2, s1, s2)
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hmono = mo_bi_ortho_one_e(p1,h1) * phase
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! alpha/beta two-body
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ispin = other_spin(s1)
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if(s1 == 1) then
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! single alpha
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do i = 1, Ne(ispin) ! electron 2
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ii = occ(i,ispin)
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htwoe += mo_bi_ortho_coul_e(ii,p1,ii,h1)
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enddo
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else
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! single beta
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do i = 1, Ne(ispin) ! electron 1
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ii = occ(i,ispin)
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htwoe += mo_bi_ortho_coul_e(p1,ii,h1,ii)
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enddo
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endif
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! same spin two-body
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do i = 1, Ne(s1)
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ii = occ(i,s1)
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! ( h1 p1 |ii ii ) - ( h1 ii | p1 ii )
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htwoe += mo_bi_ortho_coul_e(ii,p1,ii,h1) - mo_bi_ortho_coul_e(p1,ii,ii,h1)
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enddo
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htwoe *= phase
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end subroutine single_hmat_bi_ortho
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! ---
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subroutine double_hmat_bi_ortho(Nint, key_j, key_i, hmono, htwoe)
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BEGIN_DOC
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!
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! < key_j | H | key_i> for double excitation
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!
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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
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integer :: occ(Nint*bit_kind_size,2)
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integer :: Ne(2), i, j, ii, ispin, jspin
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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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integer :: other_spin(2)
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double precision :: phase
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other_spin(1) = 2
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other_spin(2) = 1
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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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if(degree .ne. 2) then
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return
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endif
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call bitstring_to_list_ab(key_i, occ, Ne, Nint)
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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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htwoe = mo_bi_ortho_coul_e(p2,p1,h2,h1)
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else
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! same spin two-body
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! direct terms exchange terms
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htwoe = mo_bi_ortho_coul_e(p2,p1,h2,h1) - mo_bi_ortho_coul_e(p1,p2,h2,h1)
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endif
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htwoe *= phase
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end subroutine double_hmat_bi_ortho
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! ---
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