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8.2 KiB
8.2 KiB
Configuration Sigma Vector Helpers
Generate the singly excited configurations on-the-fly
The algorithm is based on the work by Garniron et. al. (see thesis Chap 5). The basic idea is to generate \(|\alpha\rangle\)'s on-the-fly.
The algorithm is based on the idea of splitting the list of \(|\alpha\rangle\)'s into blocks associated with a selected determinant \(|D_I\rangle\).
Create a function to return a list of alphas
Here we create a list of \(|\alpha\rangle\)'s associated with the input determinant \(|D_I\rangle\).
subroutine obtain_associated_alphaI(idxI, Icfg, alphasIcfg, NalphaIcfg)
implicit none
use bitmasks
BEGIN_DOC
! Documentation for alphasI
! Returns the associated alpha's for
! the input configuration Icfg.
END_DOC
integer,intent(in) :: idxI ! The id of the Ith CFG
integer(bit_kind),intent(in) :: Icfg(N_int,2)
integer,intent(out) :: NalphaIcfg
integer(bit_kind),intent(out) :: alphasIcfg(N_int,2,*)
logical,dimension(:,:),allocatable :: tableUniqueAlphas
integer :: listholes(mo_num)
integer :: holetype(mo_num) ! 1-> SOMO 2->DOMO
integer :: nholes
integer :: nvmos
integer :: listvmos(mo_num)
integer :: vmotype(mo_num) ! 1 -> VMO 2 -> SOMO
integer*8 :: Idomo
integer*8 :: Isomo
integer*8 :: Jdomo
integer*8 :: Jsomo
integer*8 :: diffSOMO
integer*8 :: diffDOMO
integer :: ndiffSOMO
integer :: ndiffDOMO
integer :: ndiffAll
integer :: i
integer :: j
integer :: k
integer :: hole
integer :: p
integer :: q
integer :: countalphas
logical :: pqAlreadyGenQ
logical :: pqExistsQ
Isomo = iand(reunion_of_act_virt_bitmask(1,1),Icfg(1,1))
Idomo = iand(reunion_of_act_virt_bitmask(1,1),Icfg(1,2))
!print*,"Input cfg"
!call debug_spindet(Isomo,1)
!call debug_spindet(Idomo,1)
!print*,n_act_orb, "monum=",mo_num," n_core=",n_core_orb
! find out all pq holes possible
nholes = 0
! holes in SOMO
do i = n_core_orb+1,n_core_orb + n_act_orb
if(POPCNT(IAND(Isomo,IBSET(0,i-1))) .EQ. 1) then
nholes += 1
listholes(nholes) = i
holetype(nholes) = 1
endif
end do
! holes in DOMO
do i = n_core_orb+1,n_core_orb + n_act_orb
if(POPCNT(IAND(Idomo,IBSET(0,i-1))) .EQ. 1) then
nholes += 1
listholes(nholes) = i
holetype(nholes) = 2
endif
end do
! find vmos
listvmos = -1
vmotype = -1
nvmos = 0
do i = n_core_orb+1,n_core_orb + n_act_orb
!print *,i,IBSET(0,i-1),POPCNT(IAND(Isomo,(IBSET(0,i-1)))), POPCNT(IAND(Idomo,(IBSET(0,i-1))))
if(POPCNT(IAND(Isomo,(IBSET(0,i-1)))) .EQ. 0 .AND. POPCNT(IAND(Idomo,(IBSET(0,i-1)))) .EQ. 0) then
nvmos += 1
listvmos(nvmos) = i
vmotype(nvmos) = 1
else if(POPCNT(IAND(Isomo,(IBSET(0,i-1)))) .EQ. 1 .AND. POPCNT(IAND(Idomo,(IBSET(0,i-1)))) .EQ. 0 ) then
nvmos += 1
listvmos(nvmos) = i
vmotype(nvmos) = 2
end if
end do
!print *,"Nvmo=",nvmos
!print *,listvmos
!print *,vmotype
allocate(tableUniqueAlphas(mo_num,mo_num))
tableUniqueAlphas = .FALSE.
! Now find the allowed (p,q) excitations
Isomo = iand(reunion_of_act_virt_bitmask(1,1),Icfg(1,1))
Idomo = iand(reunion_of_act_virt_bitmask(1,1),Icfg(1,2))
!print *,"Isomo"
!call debug_spindet(Isomo,1)
!call debug_spindet(Idomo,1)
do i = 1,nholes
p = listholes(i)
do j = 1,nvmos
q = listvmos(j)
if(p == q) cycle
if(holetype(i) .EQ. 1 .AND. vmotype(j) .EQ. 1) then
! SOMO -> VMO
Jsomo = IBCLR(Isomo,p-1)
Jsomo = IBSET(Jsomo,q-1)
Jdomo = Idomo
else if(holetype(i) .EQ. 1 .AND. vmotype(j) .EQ. 2) then
! SOMO -> SOMO
Jsomo = IBCLR(Isomo,p-1)
Jsomo = IBCLR(Jsomo,q-1)
Jdomo = IBSET(Idomo,q-1)
else if(holetype(i) .EQ. 2 .AND. vmotype(j) .EQ. 1) then
! DOMO -> VMO
Jsomo = IBSET(Isomo,p-1)
Jsomo = IBSET(Jsomo,q-1)
Jdomo = IBCLR(Idomo,p-1)
else if(holetype(i) .EQ. 2 .AND. vmotype(j) .EQ. 2) then
! DOMO -> SOMO
Jsomo = IBSET(Isomo,p-1)
Jsomo = IBCLR(Jsomo,q-1)
Jdomo = IBCLR(Idomo,p-1)
Jdomo = IBSET(Jdomo,q-1)
else
print*,"Something went wrong in obtain_associated_alphaI"
endif
pqAlreadyGenQ = .FALSE.
! First check if it can be generated before
do k = 1, idxI-1
diffSOMO = XOR(Jsomo,iand(reunion_of_act_virt_bitmask(1,1),psi_configuration(1,1,k)))
diffDOMO = XOR(Jdomo,iand(reunion_of_act_virt_bitmask(1,1),psi_configuration(1,2,k)))
ndiffSOMO = POPCNT(diffSOMO)
ndiffDOMO = POPCNT(diffDOMO)
if(POPCNT(XOR(diffSOMO,diffDOMO)) .LE. 1 .AND. ndiffDOMO .LT. 3) then
pqAlreadyGenQ = .TRUE.
!print *,i,k,ndiffSOMO,ndiffDOMO
!call debug_spindet(Jsomo,1)
!call debug_spindet(Jdomo,1)
!call debug_spindet(iand(reunion_of_act_virt_bitmask(1,1),psi_configuration(1,1,k)),1)
!call debug_spindet(iand(reunion_of_act_virt_bitmask(1,1),psi_configuration(1,2,k)),1)
EXIT
endif
end do
if(pqAlreadyGenQ) cycle
pqExistsQ = .FALSE.
! now check if this exists in the selected list
do k = idxI, N_configuration
diffSOMO = XOR(OR(reunion_of_act_virt_bitmask(1,1),Jsomo),psi_configuration(1,1,k))
diffDOMO = XOR(OR(reunion_of_act_virt_bitmask(1,1),Jdomo),psi_configuration(1,2,k))
ndiffSOMO = POPCNT(diffSOMO)
ndiffDOMO = POPCNT(diffDOMO)
if((ndiffSOMO + ndiffDOMO) .EQ. 0) then
pqExistsQ = .TRUE.
EXIT
endif
end do
if(.NOT. pqExistsQ) then
tableUniqueAlphas(p,q) = .TRUE.
!print *,p,q
!call debug_spindet(Jsomo,1)
!call debug_spindet(Jdomo,1)
endif
end do
end do
!print *,tableUniqueAlphas(:,:)
! prune list of alphas
Isomo = Icfg(1,1)
Idomo = Icfg(1,2)
Jsomo = Icfg(1,1)
Jdomo = Icfg(1,2)
NalphaIcfg = 0
do i = 1, nholes
p = listholes(i)
do j = 1, nvmos
q = listvmos(j)
if(tableUniqueAlphas(p,q)) then
if(holetype(i) .EQ. 1 .AND. vmotype(j) .EQ. 1) then
! SOMO -> VMO
Jsomo = IBCLR(Isomo,p-1)
Jsomo = IBSET(Jsomo,q-1)
Jdomo = Idomo
else if(holetype(i) .EQ. 1 .AND. vmotype(j) .EQ. 2) then
! SOMO -> SOMO
Jsomo = IBCLR(Isomo,p-1)
Jsomo = IBCLR(Jsomo,q-1)
Jdomo = IBSET(Idomo,q-1)
else if(holetype(i) .EQ. 2 .AND. vmotype(j) .EQ. 1) then
! DOMO -> VMO
Jsomo = IBSET(Isomo,p-1)
Jsomo = IBSET(Jsomo,q-1)
Jdomo = IBCLR(Idomo,p-1)
else if(holetype(i) .EQ. 2 .AND. vmotype(j) .EQ. 2) then
! DOMO -> SOMO
Jsomo = IBSET(Isomo,p-1)
Jsomo = IBCLR(Jsomo,q-1)
Jdomo = IBCLR(Idomo,p-1)
Jdomo = IBSET(Jdomo,q-1)
else
print*,"Something went wrong in obtain_associated_alphaI"
endif
NalphaIcfg += 1
!print *,p,q,"|",holetype(i),vmotype(j)
!call debug_spindet(Jsomo,1)
!call debug_spindet(Jdomo,1)
alphasIcfg(1,1,NalphaIcfg) = Jsomo
alphasIcfg(1,2,NalphaIcfg) = Jdomo
endif
end do
end do
end subroutine