10
0
mirror of https://github.com/QuantumPackage/qp2.git synced 2024-10-09 17:43:12 +02:00
QuantumPackage/src/ao_one_e_ints_periodic/ao_overlap.irp.f

137 lines
3.2 KiB
Fortran

BEGIN_PROVIDER [ complex*16, ao_overlap,(ao_num,ao_num) ]
implicit none
BEGIN_DOC
! Overlap between atomic basis functions:
! :math:`\int \chi_i(r) \chi_j(r) dr)`
END_DOC
if (read_ao_integrals_overlap) then
call read_one_e_integrals_complex('ao_overlap', ao_overlap,&
size(ao_overlap,1), size(ao_overlap,2))
print *, 'AO overlap integrals read from disk'
else
print *, 'complex AO overlap integrals must be provided'
endif
END_PROVIDER
BEGIN_PROVIDER [ double precision, ao_overlap_abs,(ao_num,ao_num) ]
implicit none
BEGIN_DOC
! Overlap between absolute value of atomic basis functions:
! :math:`\int |\chi_i(r)| |\chi_j(r)| dr)`
END_DOC
integer :: i,j
!$OMP PARALLEL DO SCHEDULE(GUIDED) &
!$OMP DEFAULT(NONE) &
!$OMP PRIVATE(i,j) &
!$OMP SHARED(ao_overlap_abs,ao_overlap,ao_num)
do j=1,ao_num
do i= 1,ao_num
ao_overlap_abs(i,j)= cdabs(ao_overlap(i,j))
enddo
enddo
!$OMP END PARALLEL DO
END_PROVIDER
BEGIN_PROVIDER [ complex*16, S_inv,(ao_num,ao_num) ]
implicit none
BEGIN_DOC
! Inverse of the overlap matrix
END_DOC
call get_pseudo_inverse_complex(ao_overlap,size(ao_overlap,1),ao_num,ao_num,S_inv,size(S_inv,1))
END_PROVIDER
BEGIN_PROVIDER [ complex*16, S_half_inv, (AO_num,AO_num) ]
BEGIN_DOC
! :math:`X = S^{-1/2}` obtained by SVD
END_DOC
implicit none
integer :: num_linear_dependencies
integer :: LDA, LDC
double precision, allocatable :: D(:)
complex*16, allocatable :: U(:,:),Vt(:,:)
integer :: info, i, j, k
double precision, parameter :: threshold_overlap_AO_eigenvalues = 1.d-6
LDA = size(AO_overlap,1)
LDC = size(S_half_inv,1)
allocate( &
U(LDC,AO_num), &
Vt(LDA,AO_num), &
D(AO_num))
call svd_complex( &
AO_overlap,LDA, &
U,LDC, &
D, &
Vt,LDA, &
AO_num,AO_num)
num_linear_dependencies = 0
do i=1,AO_num
print*,D(i)
if(abs(D(i)) <= threshold_overlap_AO_eigenvalues) then
D(i) = 0.d0
num_linear_dependencies += 1
else
ASSERT (D(i) > 0.d0)
D(i) = 1.d0/sqrt(D(i))
endif
do j=1,AO_num
S_half_inv(j,i) = (0.d0,0.d0)
enddo
enddo
write(*,*) 'linear dependencies',num_linear_dependencies
do k=1,AO_num
if(D(k) /= 0.d0) then
do j=1,AO_num
do i=1,AO_num
S_half_inv(i,j) = S_half_inv(i,j) + U(i,k)*D(k)*Vt(k,j)
enddo
enddo
endif
enddo
END_PROVIDER
BEGIN_PROVIDER [ complex*16, S_half, (ao_num,ao_num) ]
implicit none
BEGIN_DOC
! :math:`S^{1/2}`
END_DOC
integer :: i,j,k
complex*16, allocatable :: U(:,:)
complex*16, allocatable :: Vt(:,:)
double precision, allocatable :: D(:)
allocate(U(ao_num,ao_num),Vt(ao_num,ao_num),D(ao_num))
call svd_complex(ao_overlap,size(ao_overlap,1),U,size(U,1),D,Vt,size(Vt,1),ao_num,ao_num)
do i=1,ao_num
D(i) = dsqrt(D(i))
do j=1,ao_num
S_half(j,i) = (0.d0,0.d0)
enddo
enddo
do k=1,ao_num
do j=1,ao_num
do i=1,ao_num
S_half(i,j) = S_half(i,j) + U(i,k)*D(k)*Vt(k,j)
enddo
enddo
enddo
deallocate(U,Vt,D)
END_PROVIDER