calc_n_parallel_excitations Function

public function calc_n_parallel_excitations(n_elecs, n_orbs, ic) result(n_parallel)

Arguments

Type IntentOptional Attributes Name
integer, intent(in) :: n_elecs
integer, intent(in) :: n_orbs
integer, intent(in) :: ic

Return Value integer


Source Code

    function calc_n_parallel_excitations(n_elecs, n_orbs, ic) result(n_parallel)
        ! this function determines the number of parallel spin excitaiton
        ! with each electrons having the same spin for a given excitation
        ! level and number of electrons and available orbitals for this spin
        integer, intent(in) :: n_elecs, n_orbs, ic
        integer :: n_parallel

        n_parallel = int(choose_i64(n_elecs, ic) * choose_i64(n_orbs - n_elecs, ic))

    end function calc_n_parallel_excitations