BSE add file

input/options

@@ -13,6 +13,6 @@
 # ACFDT: AC Kx  XBS
          F  F   T
 # BSE: BSE dBSE dTDA evDyn
-        T    T    F    F
+        T    T    T    F
 # MCMP2: nMC    nEq    nWalk dt  nPrint iSeed doDrift
          1000000 100000 10    0.3 10000 1234  T

src/QuAcK/BSE2_dynamic_perturbation_iterative.f90

@@ -0,0 +1,151 @@
+subroutine BSE2_dynamic_perturbation_iterative(dTDA,ispin,eta,nBas,nC,nO,nV,nR,nS,ERI,eHF,eGF,OmBSE,XpY,XmY)
+
+! Compute self-consistently the dynamical effects via perturbation theory for BSE2
+
+  implicit none
+  include 'parameters.h'
+
+! Input variables
+
+  logical,intent(in)            :: dTDA
+  integer,intent(in)            :: ispin
+  double precision,intent(in)   :: eta
+  integer,intent(in)            :: nBas
+  integer,intent(in)            :: nC
+  integer,intent(in)            :: nO
+  integer,intent(in)            :: nV
+  integer,intent(in)            :: nR
+  integer,intent(in)            :: nS
+
+  double precision,intent(in)   :: ERI(nBas,nBas,nBas,nBas)
+  double precision,intent(in)   :: eHF(nBas)
+  double precision,intent(in)   :: eGF(nBas)
+  double precision,intent(in)   :: OmBSE(nS)
+  double precision,intent(in)   :: XpY(nS,nS)
+  double precision,intent(in)   :: XmY(nS,nS)
+
+! Local variables
+
+  integer                       :: ia
+
+  integer,parameter             :: maxS = 10
+  double precision              :: gapGF
+
+  integer                       :: nSCF
+  integer                       :: maxSCF = 10
+  double precision              :: Conv
+  double precision              :: thresh = 1d-3
+
+
+  double precision,allocatable  :: OmDyn(:)
+  double precision,allocatable  :: ZDyn(:)
+  double precision,allocatable  :: OmOld(:)
+  double precision,allocatable  :: X(:)
+  double precision,allocatable  :: Y(:)
+
+  double precision,allocatable  ::  Ap_dyn(:,:)
+  double precision,allocatable  ::  Am_dyn(:,:)
+  double precision,allocatable  :: ZAp_dyn(:,:)
+  double precision,allocatable  :: ZAm_dyn(:,:)
+
+  double precision,allocatable  ::  B_dyn(:,:)
+
+! Memory allocation
+
+  allocate(OmDyn(nS),OmOld(nS),ZDyn(nS),X(nS),Y(nS),Ap_dyn(nS,nS),ZAp_dyn(nS,nS))
+
+  if(.not.dTDA) allocate(Am_dyn(nS,nS),ZAm_dyn(nS,nS),B_dyn(nS,nS))
+
+! Print main components of transition vectors
+
+  call print_transition_vectors(nBas,nC,nO,nV,nR,nS,OmBSE,XpY,XmY)
+
+  if(dTDA) then
+    write(*,*)
+    write(*,*) '*** dynamical TDA activated ***'
+    write(*,*)
+  end if
+
+  gapGF = eGF(nO+1) - eGF(nO) 
+
+  Conv = 1d0
+  nSCF = 0
+  OmOld(:) = OmBSE(:)
+
+  write(*,*) '---------------------------------------------------------------------------------------------------'
+  write(*,*) ' First-order dynamical correction to static Bethe-Salpeter excitation energies                     '
+  write(*,*) '---------------------------------------------------------------------------------------------------'
+  write(*,'(A57,F10.6,A3)') ' BSE2 neutral excitation must be lower than the GF gap = ',gapGF*HaToeV,' eV'
+  write(*,*) '---------------------------------------------------------------------------------------------------'
+  write(*,*)
+
+  do while(Conv > thresh .and. nSCF < maxSCF)
+
+    nSCF = nSCF + 1
+
+    write(*,*) '---------------------------------------------------------------------------------------------------'
+    write(*,'(2X,A15,I3)') 'Iteration n.',nSCF
+    write(*,*) '---------------------------------------------------------------------------------------------------'
+    write(*,'(2X,A5,1X,A20,1X,A20,1X,A20,A20)') '#','Static (eV)','Dynamic (eV)','Correction (eV)','Convergence (eV)'
+    write(*,*) '---------------------------------------------------------------------------------------------------'
+
+    do ia=1,min(nS,maxS)
+
+ 
+      X(:) = 0.5d0*(XpY(ia,:) + XmY(ia,:))
+      Y(:) = 0.5d0*(XpY(ia,:) - XmY(ia,:))
+ 
+     ! Resonant part of the BSE correction
+      call BSE2_A_matrix_dynamic(ispin,eta,nBas,nC,nO,nV,nR,nS,1d0,ERI,eGF,+OmOld(ia),Ap_dyn,ZAp_dyn)
+
+      if(dTDA) then 
+ 
+        OmDyn(ia) = dot_product(X,matmul(Ap_dyn,X))
+        ZDyn(ia)  = dot_product(X,matmul(ZAp_dyn,X))
+ 
+      else
+ 
+        ! Anti-resonant part of the BSE correction
+ 
+      call BSE2_A_matrix_dynamic(ispin,eta,nBas,nC,nO,nV,nR,nS,1d0,ERI,eGF,-OmOld(ia),Am_dyn,ZAm_dyn)
+
+      call BSE2_B_matrix_dynamic(ispin,eta,nBas,nC,nO,nV,nR,nS,1d0,ERI,eGF,B_dyn)
+
+      ZDyn(ia)  = dot_product(X,matmul(ZAp_dyn,X)) &
+                + dot_product(Y,matmul(ZAm_dyn,Y))  
+
+      OmDyn(ia) = dot_product(X,matmul(Ap_dyn,X)) &
+                - dot_product(Y,matmul(Am_dyn,Y)) &
+                + dot_product(X,matmul(B_dyn,Y))  &
+                - dot_product(Y,matmul(B_dyn,X))
+
+      end if
+ 
+      write(*,'(2X,I5,5X,F15.6,5X,F15.6,5X,F15.6,5X,F15.6)') & 
+        ia,OmBSE(ia)*HaToeV,(OmBSE(ia)+OmDyn(ia))*HaToeV,OmDyn(ia)*HaToeV,(OmBSE(ia) + OmDyn(ia) - OmOld(ia))*HaToeV
+ 
+    end do
+
+    Conv = maxval(abs(OmBSE(:) + OmDyn(:) - OmOld(:)))*HaToeV
+    OmOld(:) = OmBSE(:) + OmDyn(:)
+
+    write(*,*) '---------------------------------------------------------------------------------------------------'
+    write(*,'(2X,A20,1X,F10.6)') ' Convergence = ',Conv
+    write(*,*) '---------------------------------------------------------------------------------------------------'
+    write(*,*) 
+
+  end do
+
+! Did it actually converge?
+
+  if(nSCF == maxSCF) then
+
+    write(*,*)
+    write(*,*)'!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!'
+    write(*,*)'                 Convergence failed                 '
+    write(*,*)'!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!'
+    write(*,*)
+
+  endif
+
+end subroutine BSE2_dynamic_perturbation_iterative