quantum_package/plugins/Full_CI/target_pt2.irp.f

79 lines
2.2 KiB
Fortran

program var_pt2_ratio_run
implicit none
integer :: i,k
double precision, allocatable :: pt2(:), norm_pert(:), H_pert_diag(:)
integer :: N_st, degree
N_st = N_states
allocate (pt2(N_st), norm_pert(N_st),H_pert_diag(N_st))
character*(64) :: perturbation
double precision, allocatable :: psi_det_save(:,:,:), psi_coef_save(:,:)
double precision :: E_fci, E_var, ratio, E_ref
integer :: Nmin, Nmax
pt2 = -(pt2_max+1.d0)
diag_algorithm = "Lapack"
ratio = 0.d0
Nmin=1
do while (dabs(pt2(1)) > pt2_max)
call H_apply_FCI(pt2, norm_pert, H_pert_diag, N_st)
psi_det = psi_det_sorted
psi_coef = psi_coef_sorted
soft_touch N_det psi_det psi_coef
call diagonalize_CI
ratio = (CI_energy(1) - HF_energy) / (CI_energy(1)+pt2(1) - HF_energy)
if (N_det > 20000) then
N_det = 20000
TOUCH N_det
exit
endif
enddo
threshold_selectors = 1.d0
threshold_generators = 0.999d0
call diagonalize_CI
call H_apply_FCI_PT2(pt2, norm_pert, H_pert_diag, N_st)
E_ref = CI_energy(1) + pt2(1)
threshold_selectors = 0.99d0
threshold_generators = 0.98d0
var_pt2_ratio = (E_ref + pt2_max - HF_energy) / (E_ref - HF_energy)
TOUCH var_pt2_ratio
Nmax=max(10000,3*N_det)
Nmin=1
do while (Nmax-Nmin > 1)
ratio = (CI_energy(1) - HF_energy) / (E_ref - HF_energy)
if (ratio < var_pt2_ratio) then
Nmin = N_det
! Nmax = max(Nmax,Nmin+10)
! Select new determinants
call H_apply_FCI(pt2, norm_pert, H_pert_diag, N_st)
N_det = min(N_det,Nmax)
else
Nmax = N_det
N_det = Nmin + (Nmax-Nmin)/2
endif
psi_det = psi_det_sorted
psi_coef = psi_coef_sorted
soft_touch N_det psi_det psi_coef
call diagonalize_CI
call save_wavefunction
print *, 'Det min, Det max: ', Nmin, Nmax
print *, 'Ratio : ', ratio, ' ~ ', var_pt2_ratio
print *, 'HF_energy = ', HF_energy
print *, 'Est FCI = ', E_ref
print *, 'PT2 = ', pt2(1)
print *, 'N_det = ', N_det
print *, 'E = ', CI_energy(1)
call ezfio_set_full_ci_energy(CI_energy)
enddo
deallocate(pt2,norm_pert)
end