Livermorium (Lv). Diagram of the nuclear composition and electron configuration of an atom of livermorium-293 (atomic number: 116), the most stable isotope of this radioactive element. The nucleus consists of 116 protons (red) and 177 neutrons (yellow). 116 electrons (white) bind to the nucleus, successively occupying available electron shells (rings). Livermorium, named after the Lawrence Livermore National Laboratory and first synthesised in 2000, is a transactinide of unknown properties in group 16, period 7, and the p-block of the periodic table. The nucleus of livermorium-293 (half-life: 61 milliseconds) alpha decays to flerovium-289.