subroutine do_single_excitation_cfg(key_in,key_out,i_hole,i_particle,ok) use bitmasks implicit none BEGIN_DOC ! Applies the single excitation operator to a configuration ! If the excitation is possible, ok is True END_DOC integer, intent(in) :: i_hole,i_particle integer(bit_kind), intent(in) :: key_in(N_int,2) logical , intent(out) :: ok integer :: k,j,i integer(bit_kind) :: mask integer(bit_kind) :: key_out(N_int,2) ASSERT (i_hole > 0) ASSERT (i_particle <= mo_num) ok = .True. key_out(:,:) = key_in(:,:) ! hole k = shiftr(i_hole-1,bit_kind_shift)+1 j = i_hole-shiftl(k-1,bit_kind_shift)-1 mask = ibset(0_bit_kind,j) ! Check if the position j is singly occupied ! 1 -> 0 (SOMO) ! 0 0 (DOMO) if (iand(key_out(k,1),mask) /= 0_bit_kind) then key_out(k,1) = ibclr(key_out(k,1),j) ! Check if the position j is doubly occupied ! 0 -> 1 (SOMO) ! 1 0 (DOMO) else if (iand(key_out(k,2),mask) /= 0_bit_kind) then key_out(k,1) = ibset(key_out(k,1),j) key_out(k,2) = ibclr(key_out(k,2),j) ! The position j is unoccupied: Not OK ! 0 -> 0 (SOMO) ! 0 0 (DOMO) else ok =.False. return endif ! particle k = shiftr(i_particle-1,bit_kind_shift)+1 j = i_particle-shiftl(k-1,bit_kind_shift)-1 mask = ibset(0_bit_kind,j) ! Check if the position j is singly occupied ! 1 -> 0 (SOMO) ! 0 1 (DOMO) if (iand(key_out(k,1),mask) /= 0_bit_kind) then key_out(k,1) = ibclr(key_out(k,1),j) key_out(k,2) = ibset(key_out(k,2),j) ! Check if the position j is doubly occupied : Not OK ! 0 -> 1 (SOMO) ! 1 0 (DOMO) else if (iand(key_out(k,2),mask) /= 0_bit_kind) then ok = .False. return ! Position at j is unoccupied ! 0 -> 0 (SOMO) ! 0 0 (DOMO) else key_out(k,1) = ibset(key_out(k,1),j) endif end subroutine do_single_excitation_cfg_with_type(key_in,key_out,i_hole,i_particle,ex_type,ok) use bitmasks implicit none BEGIN_DOC ! Applies the single excitation operator to a configuration ! Returns the type of excitation in ex_type ! where the following convention is used ! 1 = (SOMO -> SOMO) 1 change in Nsomo ! 2 = (DOMO -> VMO) 1 change in Nsomo ! 3 = (SOMO -> VMO) 0 change in Nsomo ! 4 = (DOMO -> SOMO) 0 change in Nsomo ! If the excitation is possible, ok is True END_DOC integer, intent(in) :: i_hole,i_particle integer(bit_kind), intent(in) :: key_in(N_int,2) integer , intent(out) :: ex_type logical , intent(out) :: ok integer :: k,j,i integer(bit_kind) :: mask integer(bit_kind) :: key_out(N_int,2) logical :: isholeSOMO logical :: isparticleSOMO logical :: isholeDOMO logical :: isparticleVMO isholeSOMO = .False. isholeDOMO = .False. isparticleSOMO = .False. isparticleVMO = .False. ASSERT (i_hole > 0) ASSERT (i_particle <= mo_num) ok = .True. key_out(:,:) = key_in(:,:) ! hole k = shiftr(i_hole-1,bit_kind_shift)+1 j = i_hole-shiftl(k-1,bit_kind_shift)-1 mask = ibset(0_bit_kind,j) ! Check if the position j is singly occupied ! 1 -> 0 (SOMO) ! 0 0 (DOMO) if (iand(key_out(k,1),mask) /= 0_bit_kind) then key_out(k,1) = ibclr(key_out(k,1),j) isholeSOMO = .True. ! Check if the position j is doubly occupied ! 0 -> 1 (SOMO) ! 1 0 (DOMO) else if (iand(key_out(k,2),mask) /= 0_bit_kind) then key_out(k,1) = ibset(key_out(k,1),j) key_out(k,2) = ibclr(key_out(k,2),j) isholeDOMO = .True. ! The position j is unoccupied: Not OK ! 0 -> 0 (SOMO) ! 0 0 (DOMO) else ok =.False. return endif ! particle k = shiftr(i_particle-1,bit_kind_shift)+1 j = i_particle-shiftl(k-1,bit_kind_shift)-1 mask = ibset(0_bit_kind,j) ! Check if the position j is singly occupied ! 1 -> 0 (SOMO) ! 0 1 (DOMO) if (iand(key_out(k,1),mask) /= 0_bit_kind) then key_out(k,1) = ibclr(key_out(k,1),j) key_out(k,2) = ibset(key_out(k,2),j) isparticleSOMO = .True. ! Check if the position j is doubly occupied : Not OK ! 0 -> 1 (SOMO) ! 1 0 (DOMO) else if (iand(key_out(k,2),mask) /= 0_bit_kind) then ok = .False. return ! Position at j is unoccupied ! 0 -> 0 (SOMO) ! 0 0 (DOMO) else key_out(k,1) = ibset(key_out(k,1),j) isparticleVMO = .True. endif if(isholeSOMO) then ! two possibilities ! particle is SOMO or VMO if(isparticleSOMO) then ! SOMO -> SOMO ex_type = 1 else ! SOMO -> VMO ex_type = 3 endif else ! two possibilities ! particle is SOMO or VMO if(isparticleSOMO) then ! DOMO -> SOMO ex_type = 4 else ! DOMO -> VMO ex_type = 2 endif endif end subroutine generate_all_singles_cfg(cfg,singles,n_singles,Nint) implicit none use bitmasks BEGIN_DOC ! Generate all single excitation wrt a configuration ! ! n_singles : on input, max number of singles : ! elec_alpha_num * (mo_num - elec_beta_num) ! on output, number of generated singles END_DOC integer, intent(in) :: Nint integer, intent(inout) :: n_singles integer(bit_kind), intent(in) :: cfg(Nint,2) integer(bit_kind), intent(out) :: singles(Nint,2,*) integer :: i,k, n_singles_ma, i_hole, i_particle integer(bit_kind) :: single(Nint,2) logical :: i_ok n_singles = 0 !TODO !Make list of Somo and Domo for holes !Make list of Unocc and Somo for particles do i_hole = 1, mo_num do i_particle = 1, mo_num call do_single_excitation_cfg(cfg,single,i_hole,i_particle,i_ok) if (i_ok) then n_singles = n_singles + 1 do k=1,Nint singles(k,1,n_singles) = single(k,1) singles(k,2,n_singles) = single(k,2) enddo endif enddo enddo end subroutine generate_all_singles_cfg_with_type(bit_tmp,cfgInp,singles,idxs_singles,pq_singles,ex_type_singles,n_singles,Nint) implicit none use bitmasks BEGIN_DOC ! Generate all single excitation wrt a configuration ! ! n_singles : on input, max number of singles : ! elec_alpha_num * (mo_num - elec_beta_num) ! on output, number of generated singles ! ex_type_singles : on output contains type of excitations : ! END_DOC integer*8, intent(in) :: bit_tmp(0:N_configuration+1) integer, intent(in) :: Nint integer, intent(inout) :: n_singles integer, intent(out) :: idxs_singles(*) integer, intent(out) :: ex_type_singles(*) integer, intent(out) :: pq_singles(2,*) integer(bit_kind), intent(in) :: cfgInp(Nint,2) integer(bit_kind), intent(out) :: singles(Nint,2,*) integer(bit_kind) :: Jdet(Nint,2) integer :: i,k, n_singles_ma, i_hole, i_particle, ex_type, addcfg integer :: ii,kk integer(bit_kind) :: single(Nint,2) logical :: i_ok n_singles = 0 !TODO !Make list of Somo and Domo for holes !Make list of Unocc and Somo for particles !do i_hole = 1+n_core_orb, n_core_orb + n_act_orb do ii = 1, n_act_orb i_hole = list_act(ii) !do i_particle = 1+n_core_orb, n_core_orb + n_act_orb do kk = 1, n_act_orb i_particle = list_act(kk) if(i_hole .EQ. i_particle) cycle addcfg = -1 call do_single_excitation_cfg_with_type(cfgInp,single,i_hole,i_particle,ex_type,i_ok) if (i_ok) then call binary_search_cfg(single,addcfg,bit_tmp) if(addcfg .EQ. -1) cycle n_singles = n_singles + 1 do k=1,Nint singles(k,1,n_singles) = single(k,1) singles(k,2,n_singles) = single(k,2) ex_type_singles(n_singles) = ex_type pq_singles(1,n_singles) = i_hole ! p pq_singles(2,n_singles) = i_particle ! q idxs_singles(n_singles) = addcfg enddo endif enddo enddo end