mirror of
https://github.com/QuantumPackage/qp2.git
synced 2024-06-24 06:02:26 +02:00
41 lines
1.1 KiB
Fortran
41 lines
1.1 KiB
Fortran
BEGIN_PROVIDER [integer, kpt_pair_num]
|
|
implicit none
|
|
kpt_pair_num = shiftr(kpt_num*kpt_num+kpt_num,1)
|
|
END_PROVIDER
|
|
|
|
BEGIN_PROVIDER [integer, kconserv, (kpt_num,kpt_num,kpt_num)]
|
|
implicit none
|
|
BEGIN_DOC
|
|
! Information about k-point symmetry
|
|
!
|
|
! for k-points I,J,K: kconserv(I,J,K) gives L such that
|
|
! k_I + k_J = k_K + k_L
|
|
! two-electron integrals of the form <ij|kx>
|
|
! (where i,j,k have momentum k_I, k_J, k_K)
|
|
! will only be nonzero if x has momentum k_L (as described above)
|
|
!
|
|
END_DOC
|
|
integer :: i,j,k,l
|
|
|
|
if (read_kconserv) then
|
|
call ezfio_get_nuclei_kconserv(kconserv)
|
|
print *, 'kconserv read from disk'
|
|
else
|
|
print*,'kconserv must be provided'
|
|
stop -1
|
|
endif
|
|
if (write_kconserv) then
|
|
call ezfio_set_nuclei_kconserv(kconserv)
|
|
print *, 'kconserv written to disk'
|
|
endif
|
|
END_PROVIDER
|
|
|
|
subroutine double_allowed_kpts(kh1,kh2,kp1,kp2,is_allowed)
|
|
implicit none
|
|
integer, intent(in) :: kh1,kh2,kp1,kp2
|
|
logical, intent(out) :: is_allowed
|
|
|
|
is_allowed = (kconserv(kh1,kh2,kp1) == kp2)
|
|
end subroutine
|
|
|