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qp2/src/davidson_dressed/diagonalize_ci.irp.f
2019-01-25 11:39:31 +01:00

203 lines
6.9 KiB
Fortran

BEGIN_PROVIDER [ double precision, CI_energy_dressed, (N_states_diag) ]
implicit none
BEGIN_DOC
! N_states lowest eigenvalues of the CI matrix
END_DOC
integer :: j
character*(8) :: st
call write_time(6)
do j=1,min(N_det,N_states_diag)
CI_energy_dressed(j) = CI_electronic_energy_dressed(j) + nuclear_repulsion
enddo
do j=1,min(N_det,N_states)
write(st,'(I4)') j
call write_double(6,CI_energy_dressed(j),'Energy of state '//trim(st))
call write_double(6,CI_eigenvectors_s2_dressed(j),'S^2 of state '//trim(st))
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) ]
BEGIN_DOC
! Eigenvectors/values of the CI matrix
END_DOC
implicit none
double precision :: ovrlp,u_dot_v
integer :: i_good_state
integer, allocatable :: index_good_state_array(:)
logical, allocatable :: good_state_array(:)
double precision, allocatable :: s2_values_tmp(:)
integer :: i_other_state
double precision, allocatable :: eigenvectors(:,:), eigenvectors_s2(:,:), eigenvalues(:)
integer :: i_state
double precision :: e_0
integer :: i,j,k,mrcc_state
double precision, allocatable :: s2_eigvalues(:)
double precision, allocatable :: e_array(:)
integer, allocatable :: iorder(:)
PROVIDE threshold_davidson nthreads_davidson
! Guess values for the "N_states" states of the CI_eigenvectors_dressed
do j=1,min(N_states,N_det)
do i=1,N_det
CI_eigenvectors_dressed(i,j) = psi_coef(i,j)
enddo
enddo
do j=min(N_states,N_det)+1,N_states_diag
do i=1,N_det
CI_eigenvectors_dressed(i,j) = 0.d0
enddo
enddo
if (diag_algorithm == "Davidson") then
do j=1,min(N_states,N_det)
do i=1,N_det
CI_eigenvectors_dressed(i,j) = psi_coef(i,j)
enddo
enddo
call davidson_diag_HS2(psi_det,CI_eigenvectors_dressed, CI_eigenvectors_s2_dressed,&
size(CI_eigenvectors_dressed,1), CI_electronic_energy_dressed,&
N_det,min(N_det,N_states),min(N_det,N_states_diag),N_int,1)
else if (diag_algorithm == "Lapack") then
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
if (s2_eig) then
i_state = 0
allocate (s2_eigvalues(N_det))
allocate(index_good_state_array(N_det),good_state_array(N_det))
good_state_array = .False.
call u_0_S2_u_0(s2_eigvalues,eigenvectors,N_det,psi_det,N_int,&
N_det,size(eigenvectors,1))
do j=1,N_det
! Select at least n_states states with S^2 values closed to "expected_s2"
if(dabs(s2_eigvalues(j)-expected_s2).le.0.5d0)then
i_state +=1
index_good_state_array(i_state) = j
good_state_array(j) = .True.
endif
if(i_state.eq.N_states) then
exit
endif
enddo
if(i_state .ne.0)then
! Fill the first "i_state" states that have a correct S^2 value
do j = 1, i_state
do i=1,N_det
CI_eigenvectors_dressed(i,j) = eigenvectors(i,index_good_state_array(j))
enddo
CI_electronic_energy_dressed(j) = eigenvalues(index_good_state_array(j))
CI_eigenvectors_s2_dressed(j) = s2_eigvalues(index_good_state_array(j))
enddo
i_other_state = 0
do j = 1, N_det
if(good_state_array(j))cycle
i_other_state +=1
if(i_state+i_other_state.gt.n_states_diag)then
exit
endif
do i=1,N_det
CI_eigenvectors_dressed(i,i_state+i_other_state) = eigenvectors(i,j)
enddo
CI_electronic_energy_dressed(i_state+i_other_state) = eigenvalues(j)
CI_eigenvectors_s2_dressed(i_state+i_other_state) = s2_eigvalues(i_state+i_other_state)
enddo
else
print*,''
print*,'!!!!!!!! WARNING !!!!!!!!!'
print*,' Within the ',N_det,'determinants selected'
print*,' and the ',N_states_diag,'states requested'
print*,' We did not find any state with S^2 values close to ',expected_s2
print*,' We will then set the first N_states eigenvectors of the H matrix'
print*,' as the CI_eigenvectors_dressed'
print*,' You should consider more states and maybe ask for s2_eig to be .True. or just enlarge the CI space'
print*,''
do j=1,min(N_states_diag,N_det)
do i=1,N_det
CI_eigenvectors_dressed(i,j) = eigenvectors(i,j)
enddo
CI_electronic_energy_dressed(j) = eigenvalues(j)
CI_eigenvectors_s2_dressed(j) = s2_eigvalues(j)
enddo
endif
deallocate(index_good_state_array,good_state_array)
deallocate(s2_eigvalues)
else
call u_0_S2_u_0(CI_eigenvectors_s2_dressed,eigenvectors,N_det,psi_det,N_int,&
min(N_det,N_states_diag),size(eigenvectors,1))
! Select the "N_states_diag" states of lowest energy
do j=1,min(N_det,N_states_diag)
do i=1,N_det
CI_eigenvectors_dressed(i,j) = eigenvectors(i,j)
enddo
CI_electronic_energy_dressed(j) = eigenvalues(j)
enddo
endif
deallocate(eigenvectors,eigenvalues)
endif
END_PROVIDER
subroutine diagonalize_CI_dressed
implicit none
BEGIN_DOC
! Replace the coefficients of the CI states by the coefficients of the
! eigenstates of the CI matrix
END_DOC
integer :: i,j
PROVIDE delta_ij
do j=1,N_states
do i=1,N_det
psi_coef(i,j) = CI_eigenvectors_dressed(i,j)
enddo
enddo
SOFT_TOUCH psi_coef
end
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, k
h_matrix_dressed(1:N_det,1:N_det) = h_matrix_all_dets(1:N_det,1:N_det)
if (N_states == 1) then
integer :: l,jj
double precision :: f
l = dressed_column_idx(1)
f = 1.0d0/psi_coef(l,1)
do i=1,N_det
h_matrix_dressed(i,l) = h_matrix_dressed(i,l) + dressing_column_h(i,1) *f
h_matrix_dressed(l,i) = h_matrix_dressed(l,i) + dressing_column_h(i,1) *f
enddo
else
do k=1,N_states
do j=1,N_det
do i=1,N_det
h_matrix_dressed(i,j) = h_matrix_dressed(i,j) + &
dressing_column_h(i,k) * psi_coef(j,k) + &
dressing_column_h(j,k) * psi_coef(i,k)
enddo
enddo
enddo
endif
END_PROVIDER