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QCaml/Utils/Electrons.ml

32 lines
829 B
OCaml

(** Number of {% $\alpha$ %} and {% $\beta$ %} electrons *)
type t = {
n_alfa : int ;
n_beta : int ;
multiplicity : int;
}
let make ?multiplicity:(multiplicity=1) ?charge:(charge=0) nuclei =
let positive_charges =
Array.fold_left (fun accu (e, _) -> accu + Charge.to_int (Element.to_charge e) )
0 nuclei
in
let negative_charges = charge - positive_charges in
let n_elec = - negative_charges in
let n_beta = ((n_elec - multiplicity)+1)/2 in
let n_alfa = n_elec - n_beta in
let result = { n_alfa ; n_beta ; multiplicity } in
if multiplicity <> (n_alfa - n_beta)+1 then
invalid_arg (__FILE__^": make");
result
let charge e =
- (e.n_alfa + e.n_beta)
|> Charge.of_int
let n_alfa t = t.n_alfa
let n_beta t = t.n_beta
let n_elec t = t.n_alfa + t.n_beta
let multiplicity t = t.multiplicity