unsur 138Namun, setelah unsur 120, pengisian konfurasi elektronik berhenti mematuhi prinsip Auau. Menurut prinsipnya, unpenttrium harus memiliki konfurasi elektronik [Og]8s 2 5g 18 6f 14 7dThe following table shows the atomic nuclei that are isotonic (same neutron number N = 81) and isobaric (same nucleon number A = 138) with Lanthanum-138. Naturally occurring isotopes