quantum_package/src/MRCC/mrcc_dress.irp.f

191 lines
5.4 KiB
Fortran

subroutine mrcc_dress(delta_ij_sd_,Ndet_sd,i_generator,n_selected,det_buffer,Nint,iproc)
use bitmasks
implicit none
integer, intent(in) :: i_generator,n_selected, Nint, iproc
integer, intent(in) :: Ndet_sd
double precision, intent(inout) :: delta_ij_sd_(Ndet_sd,Ndet_sd,*)
integer(bit_kind), intent(in) :: det_buffer(Nint,2,n_selected)
integer :: i,j,k,m
integer :: new_size
logical :: is_in_wavefunction
integer :: degree(psi_det_size)
integer :: idx(0:psi_det_size)
logical :: good
integer(bit_kind) :: tq(Nint,2,n_selected)
integer :: N_tq, c_ref
integer :: connected_to_ref
N_tq = 0
do i=1,N_selected
c_ref = connected_to_ref(det_buffer(1,1,i),psi_det_generators,Nint, &
i_generator,N_det_generators)
if (c_ref /= 0) then
cycle
endif
! Select determinants that are triple or quadruple excitations
! from the CAS
good = .True.
call get_excitation_degree_vector(psi_cas,det_buffer(1,1,i),degree,Nint,N_det_cas,idx)
do k=1,idx(0)
if (degree(k) < 3) then
good = .False.
exit
endif
enddo
if (good) then
if (.not. is_in_wavefunction(det_buffer(1,1,i),Nint,N_det)) then
N_tq += 1
do k=1,N_int
tq(k,1,N_tq) = det_buffer(k,1,i)
tq(k,2,N_tq) = det_buffer(k,2,i)
enddo
endif
endif
enddo
! Compute <k|H|a><a|H|j> / (E0 - Haa)
double precision :: hka, haa
double precision :: haj
double precision :: f(N_states)
do i=1,N_tq
call get_excitation_degree_vector(psi_sd,tq(1,1,i),degree,Nint,Ndet_sd,idx)
call i_h_j(tq(1,1,i),tq(1,1,i),Nint,haa)
do m=1,N_states
f(m) = 1.d0/(ci_electronic_energy(m)-haa)
enddo
do k=1,idx(0)
call i_h_j(tq(1,1,i),psi_sd(1,1,idx(k)),Nint,hka)
do j=k,idx(0)
call i_h_j(tq(1,1,i),psi_sd(1,1,idx(j)),Nint,haj)
do m=1,N_states
delta_ij_sd_(idx(k), idx(j),m) += haj*hka* f(m)
delta_ij_sd_(idx(j), idx(k),m) += haj*hka* f(m)
enddo
enddo
enddo
enddo
end
BEGIN_PROVIDER [ double precision, delta_ij_sd, (N_det_sd, N_det_sd,N_states) ]
implicit none
BEGIN_DOC
! Dressing matrix in SD basis
END_DOC
delta_ij_sd = 0.d0
call H_apply_mrcc(delta_ij_sd,N_det_sd)
END_PROVIDER
BEGIN_PROVIDER [ double precision, delta_ij, (N_det,N_det,N_states) ]
implicit none
BEGIN_DOC
! Dressing matrix in N_det basis
END_DOC
integer :: i,j,m
delta_ij = 0.d0
do m=1,N_states
do j=1,N_det_sd
do i=1,N_det_sd
delta_ij(idx_sd(i),idx_sd(j),m) = delta_ij_sd(i,j,m)
enddo
enddo
enddo
END_PROVIDER
BEGIN_PROVIDER [ double precision, h_matrix_dressed, (N_det,N_det) ]
implicit none
BEGIN_DOC
! Dressed H with Delta_ij
END_DOC
integer :: i, j
do j=1,N_det
do i=1,N_det
h_matrix_dressed(i,j) = h_matrix_all_dets(i,j) + delta_ij(i,j,1)
if (i==j) then
print *, i, delta_ij(i,j,1), h_matrix_all_dets(i,j)
endif
enddo
enddo
END_PROVIDER
BEGIN_PROVIDER [ double precision, CI_electronic_energy_dressed, (N_states_diag) ]
&BEGIN_PROVIDER [ double precision, CI_eigenvectors_dressed, (N_det,N_states_diag) ]
&BEGIN_PROVIDER [ double precision, CI_eigenvectors_s2_dressed, (N_states_diag) ]
implicit none
BEGIN_DOC
! Eigenvectors/values of the CI matrix
END_DOC
integer :: i,j
do j=1,N_states_diag
do i=1,N_det
CI_eigenvectors_dressed(i,j) = psi_coef(i,j)
enddo
enddo
if (diag_algorithm == "Davidson") then
stop 'use Lapack'
! call davidson_diag(psi_det,CI_eigenvectors_dressed,CI_electronic_energy_dressed, &
! size(CI_eigenvectors_dressed,1),N_det,N_states_diag,N_int,output_Dets)
else if (diag_algorithm == "Lapack") then
double precision, allocatable :: eigenvectors(:,:), eigenvalues(:)
allocate (eigenvectors(size(H_matrix_dressed,1),N_det))
allocate (eigenvalues(N_det))
call lapack_diag(eigenvalues,eigenvectors, &
H_matrix_dressed,size(H_matrix_dressed,1),N_det)
CI_electronic_energy_dressed(:) = 0.d0
do i=1,N_det
CI_eigenvectors_dressed(i,1) = eigenvectors(i,1)
enddo
integer :: i_state
double precision :: s2
i_state = 0
do j=1,N_det
call get_s2_u0(psi_det,eigenvectors(1,j),N_det,N_det,s2)
if(dabs(s2-expected_s2).le.0.3d0)then
i_state += 1
do i=1,N_det
CI_eigenvectors_dressed(i,i_state) = eigenvectors(i,j)
enddo
CI_electronic_energy_dressed(i_state) = eigenvalues(j)
CI_eigenvectors_s2_dressed(i_state) = s2
endif
if (i_state.ge.N_states_diag) then
exit
endif
enddo
deallocate(eigenvectors,eigenvalues)
endif
END_PROVIDER
BEGIN_PROVIDER [ double precision, CI_energy_dressed, (N_states_diag) ]
implicit none
BEGIN_DOC
! N_states lowest eigenvalues of the dressed CI matrix
END_DOC
integer :: j
character*(8) :: st
call write_time(output_Dets)
do j=1,N_states_diag
CI_energy_dressed(j) = CI_electronic_energy_dressed(j) + nuclear_repulsion
write(st,'(I4)') j
call write_double(output_Dets,CI_energy(j),'Energy of state '//trim(st))
call write_double(output_Dets,CI_eigenvectors_s2(j),'S^2 of state '//trim(st))
enddo
END_PROVIDER