Livermorium at a glance
- Atomic number
- 116
- Symbol
- Lv
- Atomic mass
- 293 u
- Category
- Post-transition metal
- Group / period
- 16 / 7
- Electron configuration
- [Rn] 5f 14 6d 10 7s 2 7p 4
- State at 25 °C
- Unknown
- Melting point
- n/a
- Boiling point
- n/a
- Density
- 12.9 g/cm³
- Electronegativity
- n/a
- 1st ionization energy
- 664 kJ/mol
- Oxidation states
- n/a
- Discovered
- 2000
Atomic structure
A neutral livermorium atom has 116 protons and 116 electrons, and its most common isotope carries about 177 neutrons. One atom weighs about 4.87 × 10⁻²⁵ kg, so a mole of livermorium (6.022 × 10²³ atoms) weighs 293 g. That nucleus holds 1.53 neutrons for every proton, typical of heavy nuclei, which need extra neutrons to hold together against the protons' repulsion. The electrons fill 7 shells (K 2, L 8, M 18, N 32, O 32, P 18, Q 6), which gives the configuration [Rn] 5f 14 6d 10 7s 2 7p 4. With 6 electrons in its outer shell, it tends to gain or share electrons to complete its outer shell. Every isotope is radioactive and short-lived; only a handful of atoms have ever been made, one at a time.
Physical properties
So little livermorium has ever existed at once that its melting point, boiling point and even its state at room temperature are unknown. Its density is 12.9 g/cm³ (predicted), 12.9 times as dense as water.
Chemical behaviour
It has no measured electronegativity. Pulling off its outermost electron takes 664 kJ/mol (predicted), less than Polonium above it (812 kJ/mol). Group 16 also holds Oxygen, Sulfur, Selenium, Tellurium and Polonium, which share its outer-shell pattern. Its Lewis symbol is Lv surrounded by 6 dots. Handle with care: as a pure element it is radioactive.
Where it comes from
It does not occur in nature in useful amounts; it is made in nuclear reactors or particle accelerators. It was first made at Dubna, with Lawrence Livermore by fusing curium-248 with calcium-48. Its longest-lived known isotope is Lv-293, about 60 milliseconds. It was first identified in 2000, making it the 114th element to be discovered (counting the 11 known since antiquity together).