mirror of
https://github.com/pfloos/quack
synced 2024-10-18 05:51:47 +02:00
29 lines
753 B
Fortran
29 lines
753 B
Fortran
recursive function HRROv(AngMomA,AngMomB,ExpPi,CenterAB,CenterPA) &
|
|
result(Gab)
|
|
|
|
! Horizontal recurrence relations for one-electron overlap integrals
|
|
|
|
implicit none
|
|
|
|
! Input variables
|
|
integer,intent(in) :: AngMomA,AngMomB
|
|
double precision,intent(in) :: ExpPi
|
|
double precision,intent(in) :: CenterAB,CenterPA
|
|
|
|
! Local variables
|
|
double precision :: VRROv
|
|
double precision :: Gab
|
|
|
|
if(AngMomB < 0) then
|
|
Gab = 0d0
|
|
else
|
|
if(AngMomB == 0) then
|
|
Gab = VRROv(AngMomA,ExpPi,CenterPA)
|
|
else
|
|
Gab = HRROv(AngMomA+1,AngMomB-1,ExpPi,CenterAB,CenterPA) &
|
|
+ CenterAB*HRROv(AngMomA,AngMomB-1,ExpPi,CenterAB,CenterPA)
|
|
end if
|
|
end if
|
|
|
|
end function HRROv
|