realangularintegral Function

public pure function realangularintegral(a_l, a_i1, a_i2, a_i3, a_i4) result(aintegral)

This function computes the double angular integral (real spherical harmonics)

4pi/(2 l+1) sum_m int d Omega Y_lm^* Y_l1m1 Y_l3m3 int d Omega Y_lm Y_l2m2 Y_l4m4

Arguments

Type	Intent	Optional	Attributes		Name
integer,	intent(in)			::	a_l	l quantum number
type(atomorbital),	intent(in)			::	a_i1	set of l,m quantum numbers
type(atomorbital),	intent(in)			::	a_i2	set of l,m quantum numbers
type(atomorbital),	intent(in)			::	a_i3	set of l,m quantum numbers
type(atomorbital),	intent(in)			::	a_i4	set of l,m quantum numbers

Return Value real(kind=long)